Answer:
D
Explanation:
She says that the object of the experiment is to see how far the string stretches given a mass attached to the string.
The only thing that is at issue is either the mass or the amount the string stretches.
Nothing else matters.
The dependent variable therefore is the amount the string stretches. So the last choice is the answer.
A block and tackle consisting of 5 pulleys is used to raised a load of 400N through a height of 10m.If the work done against friction is 100j.
Calculate;
1)The work done by the effort
2)The efficiency of the system
3)The effort applied
Answer:
1) 4000Joules
2) 25%
3) 320N
Explanation:
A block and tackle consisting of 5 pulleys is used to raised a load of 400N through a height of 10m.If the work done against friction is 100j.
Calculate;
1)The work done by the effort
2)The efficiency of the system
3)The effort applied
1) Workdone by the effort is the work input = Load * distance moved by the Load
Workdone by the effort = 400 * 10
Workdone by the effort = 4000Joules
2) Efficiency = Work output/Work input * 100
Work output = work done against friction = 100 Joules
Efficiency = 100/4000 * 100
Efficiency = 10000/4000
Efficiency = 25%
Hence the Efficiency of the system is 25%
3) Using the efficiency formula:
efficiency = MA/VR * 100
Velocity ratio = 5
MA = Load/Effort
efficiency = (L/E)/5 * 100
25 = 400/E/5 * 100
25/100 = 400/5E
0.25 = 400/5E
0.25 * 5E = 400
1.25E = 400
E = 400/1.25
E = 320N
hence the effort applies is 320N
A runner exerts a net force of 335 n to accelerate at a rate of 2.5 m/s what is the runners mass
Electricity from the local power company costs 5.79 cents/kWh. How much would it cost to run a 120-W stereo system for 4.0 hours per day for 4.0 weeks?
A. $1.33
B. $0.78
C. $0.11
D. $2.18
Answer:
Answer: B. $0.78.
Explanation:
Cost of Electricity
The rate of the cost of electricity is usually expressed in $/kWh or cents/kWh because the consumption of electricity is measured in Kilowatts-hour.
The local power company charges 5.79 cents/kWh.
We are required to calculate the cost to run a 120 W stereo system for 4 hours per day for 4 weeks.
The total consumption time is 4 hours/day * 7 days/week *4 weeks = 112 hours
The total energy consumed is 120 W * 112 h =13,440 Wh.
Converting to kWh: 13,440 Wh/1,000 = 13.440 kWh.
Finally, we multiply by the cost rate: 5.79 cents/kWh * 13.440 kWh = 77.8 cents/100 = $0.78.
Answer: B. $0.78.
plzzzz help me will mark u brainiest
Answer:
D
Explanation:
Under what circumstances will the projectile have the greatest velocity when it hits the ground? Explain please
Laws of motion
Laws of motion
Answer:
Newton's laws of motion are three physical laws that, together, laid the foundation for classical mechanics. They describe the relationship between a body and the forces acting upon it, and its motion in response to those forces.
Explanation:
What are Newton's 1st 2nd and 3rd laws of motion?
In the first law, an object will not change its motion unless a force acts on it. In the second law, the force on an object is equal to its mass times its acceleration. In the third law, when two objects interact, they apply forces to each other of equal magnitude and opposite direction.
Any force that resists motion and causes heat
Answer: Two objects sliding against each other.
Explanation:
The friction between the two surfaces converts kinetic energy into heat.
12. The diameter of a circle is 2.42m. Calculate its
area in proper significant figure
Answer:
A = 4.6 [m²]
Explanation:
The area of a circle can be calculated by means of the following equation.
[tex]A=\frac{\pi }{4} *D^{2}[/tex]
where:
A = area [m²]
D = diameter = 2.42 [m]
Now replacing:
[tex]A=\frac{\pi }{4} *(2.42)^{2} \\A = 4.6 [m^{2} ][/tex]
Which of the following does not illustrate a complete circuit?
Answer:
I think A
Explanation:
because it dosn't have enough tools
What is 2 + 2 i have been stuff on this for weeks
Answer:
4..... the answer is 4
Explanation:
A pinball bangs against a bumper of a pinball machine with a speed of 0.46 m/s. If the ball has a mass of 0.058 kg, what is the ball's kinetic energy?
This needs to be done in 3 mins
Answer:
Okay I might be wrong and sorry if i am either its 12 or 0.402
Explanation:
* I recommend the second one cause its more logical
Be aware I might be wrong
the ocean contains many plants and protists that can make their own food through photosynthesis. Which need do these organisms get by living near the surface that they cannot get in deep water?
shelter
oxygen
sunlight
Answer:
sunlight
Explanation:
Photosynthesis is made possible by energy from the sun.
A merry go round exerts a force of 1000 N on a rider on the
outer ring of animals when it takes 15 seconds to make a
complete revolution. If the person weighs 750 N, the radius
of the circle he is making is m. Round your answer to
the nearest tenth.
Answer:
The radius of the circle made by the person on the merry go round is 74.55 meters
Explanation:
The given parameters are;
The force the merry go round exerts on the rider = 1000 N
The time it takes the merry go round to make one complete revolution = 15 seconds
The weight of the person = 750 N
The radius of the circle made by the person on the merry go round = r
We have;
[tex]F_c = \dfrac{m \cdot v^2}{r} = m \cdot \omega ^2 \cdot r[/tex]
Where;
m = The mass of the person
v = The velocity of the person
[tex]F_c[/tex] = The centrifugal force acting on the person = 1,000 N
r = The radius of the circle made by the person on the merry go round
ω = Angular velocity = 2·π/15 rad/s
We have;
The mass of the person = The weight/(The acceleration due to gravity, g)
∴ The mass of the person = 750/9.81 ≈ 76.45 kg
By substituting the calculated and known values into the equation for the centripetal force, we have;
[tex]F_c[/tex] = m × ω² × r
1000 = 76.45 × (2·π/15)² × r
r = 1000/(76.45 × (2·π/15)²) = 74.55 m
The radius of the circle made by the person on the merry go round = r = 74.55 m.
a solid sphere and a hollow sphere having same destiny and radius are rolling down an inclined plane. which one of them will reach first ?
Answer:
The solid sphere.
Explanation:
The moment of inertia for hollow sphere is larger, thereby having a greater resistance to motion. Thus the solid sphere will have greater speed.
Answer:
The solid sphere
Explanation:
So when comparing the spheres, both spheres have the same density and have the same radius which would they are the same size so the only factor to vary them is mass. The solid sphere is filled and thus heavier compared to the hollow sphere which has lighter air. As a result, the solid sphere will be pulled down by gravity more and reach the bottom first.
Please answer ASAP!!!! Which statement describes the factors that affect the force of a spring?
A. The spring force depends on the spring constant, and increases as displacement
increases
B. The spring force only depends on the spring constant
C. The spring force gets weaker as displacement increases, and is in the same
direction as the displacement
D. The spring force depends on gravity and friction
Answer:
d
Explanation:
the spring depends on gravity and friction
5) A 20.0 kg cart with no friction wheels sits on a table. A light string is attached to it and runs over a low friction pulley to a 0.0150 kg mass.
Draw a free body diagram showing all the forces acting on each object
Calculate the acceleration of the masses
Calculate the tension force in the cord
How long will it take the block to get to go 1.2 m to the edge of the table.
What will the velocity be as soon as it gets to the edge?
Answer:
1) Please find attached, created with Microsoft Visio
2) The acceleration of the masses connected by the light string is 0.00735 m/s²
3) The tension in the cord is 0.147 N
4) The time it would take the block to go 1.2 m to the edge of the table is approximately 18.07 s
5) The velocity of the cart as soon as it gets to the edge of the table is 0.042 m/s
Explanation:
1) Please find attached, the required free body diagram, showing the tension, weight and frictional (zero friction) forces acting on the cart and the mass created with Microsoft Visio
2) The acceleration of the masses connected by the light string is given as follows;
F = Mass, m × Acceleration, a
The mass of the truck, M = 20.0 kg
The mass attached to the string, hanging rom the pulley, m = 0.0150 kg
The force, F acting on the system = The pulling force on the cart = The tension on the cable = The weight of the hanging mass = 0.0150 × 9.8 = 0.147 N
The pulling force acting on the cart, F = M × a
∴ F = 0.147 N = 20.0 kg × a
a = 0.147 N/(20.0 kg) = 0.00735 m/s²
The acceleration of the truck = a = 0.00735 m/s²
3) The tension in the cord = F = 0.147 N
4) The time, t, it would take the block to go 1.2 m to the edge of the table is given by the kinematic equation, s = u·t + 1/2·a·t²
Where;
s = The distance to the edge of the table = 1.2 m
u = The initial velocity = 0 m/s (The cart is assumed to be initially at rest)
a = The acceleration of the cart = 0.00735 m/s²
t = The time taken
Substituting the known values, gives;
s = u·t + 1/2·a·t²
1.2 = 0 × t + 1/2 ×0.00735 × t²
1.2 = 1/2 ×0.00735 × t²
t² = 1.2/(1/2 ×0.00735) ≈ 326.5306
t = √(1.2/(1/2 ×0.00735)) ≈ 18.07
The time it would take the block to go 1.2 m to the edge of the table = t ≈ 18.07 s
5) The velocity, v, of the cart as soon as it gets to the edge of the table is given by the kinematic equation, v² = u² + 2·a·s as follows;
v² = u² + 2·a·s
u = 0 m/s
v² = 0² + 2 × 0.00735 × 1.2 = 0.001764
v = √(0.001764) = 0.042
The velocity of the cart as soon as it gets to the edge of the table = v = 0.042 m/s.
Answer:
There's no answer I'm just taking points like you did me, so thank you for your points I'll put them to good use ;)
A boy throws a stone vertically in the air with an initial speed of 40m/sec.At the instant the stone is thrown,a monkey at the top of a tree h m high falls freely.How long will it take for the stone to hit the monkey if they meet at a point mid way between the ground and the top of tree?
∞infinaty stones∞
because why not
25 points and i will give brainliest +5 star rating to a correct a correct answer!!!!
Green light (520 nm) enters glass with n = 1.52. What is speed of light in the glass?
Answer:
1.97 * 10^8 m/s
Explanation:
Given that:
n = 1.52
Recall : speed of light (c) = 3 * 10^8 m/s
Speed (v) of light in glass:
v = speed of light / n
v = (3 * 10^8) / 1.52
v = 1.9736 * 10^8
Hence, speed of light in glass :
v = 1.97 * 10^8 m/s
HELP! WILL GIVE BRAINLIST!!!
- How do the greenhouse gases warm the atmosphere?
a. Solar radiation penetrates the atmosphere and is trapped by greenhouse gases which warms the atmosphere.
b. Solar radiation is absorbed by the Earth which directly warms the atmosphere.
c. Infrared radiation from the Sun is trapped by greenhouses gases and heats the atmosphere.
d. Solar radiation absorbed by the Earth is converted to infrared which is blocked by greenhouse gases and heats the atmosphere.
Answer:
Explanation:
Option C is the correct answer
Infrared radiation from the Sun is trapped by greenhouse gases and heats the atmosphere, by this phenomenon of heat absorption the greenhouse gases warm the atmosphere,therefore the correct answer is option C.
What is electromagnetic radiation?The propagation of electromagnetic waves, which are generated from both natural and artificial sources, results in the energy radiation known as electromagnetic radiation.
This radiation does not need any kind of medium to propagate. The electromagnetic wave has components of light as well as heat in them.
By absorbing heat through the process of heat assimilation, greenhouse gases warm the atmosphere by trapping infrared light from the Sun.
Thus, the correct answer is option C.
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A washing machine is being dragged with a starting force of 380.8 N to the West, but this is reduced by friction. If the mass of the washing machine is 37 kg
and the coefficient of friction is 0.54, what was the Net acceleration experienced by the washing machine?
A 10.27 m/s^2 South
B 5 m/s^2 South
C 19.01 m/s^2 South
D 7.6 m/s^2 South
Answer:
B. [tex]5\,\frac{m}{s^{2}}[/tex] South
Explanation:
The correct statement is:
A washing machine is being dragged with a starting force of 380.8 N to the South, but this is reduced by friction. If the mass of the washing machine is 37 kg and the coefficient of friction is 0.54, what was the Net acceleration experienced by the washing machine?
The net force of the washing machine moving on the horizontal ground is equal to the external force minus the friction force, where the normal force from the ground on the washing machine is equal to its weight. The free body diagram of the washing machine is presented below. The equation of equilibrium associated with the acceleration of the washing machine is:
[tex]\Sigma F = P -\mu_{k}\cdot m \cdot g = m\cdot a[/tex] (1)
Where:
[tex]P[/tex] - External force exerted on the washing machine, measured in newtons.
[tex]\mu_{k}[/tex] - Kinetic coefficient of friction, dimensionless.
[tex]m[/tex] - Mass, measured in kilograms.
[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.
[tex]a[/tex] - Net acceleration of the washing machine.
If we know that [tex]P = 380.8\,N[/tex], [tex]m = 37\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex] and [tex]\mu_{k} = 0.54[/tex], then the net acceleration experienced by the washing machine is:
[tex]a = \frac{P}{m}-\mu_{k}\cdot g[/tex]
[tex]a = \frac{380.8\,N}{37\,kg}-(0.54)\cdot \left(9.807\,\frac{m}{s^{2}} \right)[/tex]
[tex]a = 4.996\,\frac{m}{s^{2}}[/tex]
The correct answer is B.
A bus accelerates forward. If an apple were on the floor of the bus it would move forward.
A: True
B: False
Answer:
False
Explanation:
Since it is on the bus, it would not move forward because the outside acceleration cannot be considered.
In raising an object vertically at a constant speed of 2 m / s 10 watts of power is developed the weight of the object is
Answer:
5NExplanation:
Power = Workdone/Time
Since workdone = Force * distance = mgh
Power = mgh/t
Given
Power = 10watts
speed = 2m/s
Power = Weight * velocity
Substitute
10 = Weight * 2
Weight = 10/2
Weight = 5N
Hence the weight of the object is 5N
Who was the first person to study polarization of light?
-Huygens
-Newton
-Galileo
-Copernicus
Answer:
HUYGENS, CAN I S HAVE BRAINLIST?
Answer:
None
Explanation:
It is erasmus bartholinus
How cold is it in texas rn?
Answer:
cold
Explanation:
A football player at practice pushes a 80 kg blocking sled across the field at a constant speed. The coefficient of kinetic friction between the grass and the sled is 0.30. How much force must he apply to the sled
Answer:
The value is [tex]F = 235.2 \ N[/tex]
Explanation:
From the question we are told that
The mass of the sled is [tex]m = 80 \ kg[/tex]
The coefficient of friction is [tex]\mu = 0.30[/tex]
Generally the force that must be applied to the sled is equal to the frictional force experienced by the sled which is mathematically represented as
[tex]F = m * \mu * g[/tex]
=> [tex]F = 80 * 0.30 * 9.8[/tex]
=> [tex]F = 235.2 \ N[/tex]
A mosquito can fly with a speed of 1.10 m/s with respect to the air. Suppose a mosquito flies east at this speed across a swamp. The mosquito is flying into a breeze that has a velocity of 1.4 m/s with respect to Earth and moves in the direction of 35 west of south. What is the mosquito's speed with respect to the Earth?
Answer:
The velocity of Mosquito with respect to earth will be 0.302m/s
Explanation:
V(ma) = 1.10 m/s, east Velocity of mosquito with respect to air
V(ae) = 1.4 m/s at 35° Velocity of air with respect to Earth in west of south direction.
Velocity of Mosquito with respect to earth will be
V(me) = V(ma) + V(ae)
We need to find the mosquito’s speed with respect to Earth in the x direction.
V(x, me) = V(x, ma) + V(x, ae) = V(ma) + V(ae)(cos theta(ae) )
Angle (ae) = –90.0° − 35°=−125°
V(x, me) = 1.10 + (1.4)Cos(-125)
= 1.10 + 1.4(-0.57)
= 1.10 -0.798
= 0.302
So the velocity of Mosquito with respect to earth will be 0.302m/s
The chart below lists the densities of various gemstones. If a gemstone has a mass of 6.24 g and a volume of 1.98 cm cubed, which gemstone is it
A. Opal
B. Diamond
C. Garnet
D. Topaz
Answer:
C. Garnet
Explanation:
density = mass/volume
density = 6.24g/1.98cm^3
density = 3.15 g/cm^3 (Garnet)
Hope this helps!
Garnets are minerals that can be found as single crystals, pebble-like formations, or masses of intergrown crystals.They are opaque, transparent to translucent minerals. Thus, option C is correct.
What are the physical properties of Garnet?A garnet has a volume of 1.6 cubic centimetres and a density of 3.5 grams per cubic centimetre. The proportion of a mineral's mass to volume is known as density. It is a measurement of how much “stuff” can fit into the space a mineral takes up.
Garnets can be found in a variety of colours, including orange, yellow, green, purple, brown, blue, black, pink, and colorless, but are most usually found in reddish tones.There are very few blue garnets.
Therefore, density = mass/volume density = 6.24g/1.98 cm^3 density = 3.15 g/cm^3 (Garnet).
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Do you think the inner planets should be explored or should the money be spent on other things? Justify your opinion.
Answer:
yes i think that inner planets should be explored because if we ever find new life or are able to live there then i think its worth takeing a risk.
Explanation:
Which statement best explains why Earth’s outer core is in liquid form? The iron-nickel alloy melts due to hot temperatures. The outer core has a tarry consistency. This region is less dense when compared to the mantle. This region is under extreme pressure from the weight of other layers.
Answer:
I took the science quiz and Its A
Explanation:
HOPE THIS HELPS!
The iron-nickel alloy melts due to hot temperatures. This statement best explains why Earth’s outer core is in liquid form
Where is the outer core?The Earth's outer core is the second innermost layer, located between the inner core and the mantle. It contains mostly iron and nickel, which- due to lower pressure than existing at the inner core- are in the liquid form. The outer core, about 2,200 kilometers (1,367 miles) thick, is mostly composed of liquid iron and nickel because of the high temperature. However, the intense pressure, which increases towards the inner core, dramatically changes the melting point of the nickel–iron, making it solid. The iron and nickel alloy of the outer core is very hot, between 4,500° and 5,500° Celsius (8,132° and 9,932° Fahrenheit).
The outer core is a liquid alloy of mainly iron and nickel. The reason why the core is metal is that the heavy metals sank to the center while the Earth was cooling. The mantle which lies above the core is made of molten rock
correct option is a) The iron-nickel alloy melts due to hot temperatures.
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The main difference between distance and displacement is tat
Answer:
Distance is the length of the path taken by an object whereas displacement is the simply the distance between where the object started and where it ended up.
Explanation:
Hope this helps! Good Luck on the rest of your assignments! :)
Answer:
Distance is quite literally the total amount of distance you have covered. Displacement is the total displacement from your origin. For example, if you were to move 5m north then 2m south, your total displacement from your origin would be 3m north.