Answer: Only foam rubber is compressible material
Explanation:
The pillow is made up of foam rubber which can be compressed easily due to the soft compressible rubber with hands on application of pressure on the surface. The shape of pillow regain its original shape when the pressure is withdrawn from the pillow. If the same activity is performed on the piece of rectangular block of wood and plasticine. Then the rectangular block of wood cannot be compressed with hand as it is a solid body. Plasticine is a putty like material. It is a clay like material and it can be compressed with hand but when the pressure is withdrawn the plasticine does not regain its shape back.
Find the density of a solid object whose mass is 315g, given that its length is 7cm,
width is 3cm and height is 5cm. b) State the unit for measuring density.
Thanks for helping
Answer:
Density is the mass of an object divided by its volume. ... Density often has units of grams per cubic centimeter ... Density is not something that is directly measured.
Explanation:
given
mass (m) = 315 g
length (l) = 7 cm
width (b) = 3 cm
height (h) = 5 cm
Now
volume (v) = l * b * h
V = 7 * 3 * 5
V = 105 cm³
Density (d) = ?
We know
density is defined as mass per unit volume so
d = m / v
d = 315 / 105
d = 3 g/cm³
Therefore density = 3 g/cm³
Note
If the question is asked to write in SI unit of density then u have to write the unit of density as kg/m³
Hope it will help :)
(a) Explain the advantage of using a plane mirror in optical testing.
explain your answer
Answer: Optical test is a test which is used to assess vision and ability of the person to focus on the objects.
Explanation:
The following are the advantages of utilizing plane mirror in optical testing:
1. When a plane mirror is used for testing the image of the test card must be placed at distance equal to the distance of the object.
2. Larger distance in between the object or test card and viewer is obtained. This can help in determining the exact ability of the eye to focus on objects.
10.
A simple pendulum set into vibration
completes an oscillation in time T. If
the length of the pendulum is
increased to 9 times its original
length, the new period of oscillation in
terms of T will be
А. 18.0 T
B. 9.0 T.
C. 4.5 T.
D 3.0 T
E. 0.1 T.
Answer:
The new period of oscillation is D) 3.0 T
Explanation:
Simple Pendulum
A simple pendulum is a mechanical arrangement that describes periodic motion. The simple pendulum is made of a small bob of mass 'm' suspended by a thin inextensible string.
The period of a simple pendulum is given by
[tex]T=2\pi \sqrt{\frac{L}{g}}[/tex]
Where L is its length and g is the local acceleration of gravity.
If the length of the pendulum was increased to 9 times (L'=9L), the new period of oscillation will be:
[tex]T'=2\pi \sqrt{\frac{L'}{g}}[/tex]
[tex]T'=2\pi \sqrt{\frac{9L}{g}}[/tex]
Taking out the square root of 9 (3):
[tex]T'=3*2\pi \sqrt{\frac{L}{g}}[/tex]
Substituting the original T:
[tex]T'=3*T[/tex]
The new period of oscillation is D) 3.0 T
This is very hard, I don't understand.
Answer:
[tex]4x - 6 = 90 \\ 4x = 96 \\ \boxed{x = 24}[/tex]
Now, AD is an altitude of∆ABC
Therefore, D is the midpoint of BC
[tex]x + 7 = 2x - 15 \\ \boxed{x = 22}[/tex]
CD is (22+7) = 29 & DB is (2×22-15) = 29
[tex] \huge \boxed{\: x = 24 }\\ \huge \boxed{CD \: and \:DB= 29}[/tex]
velocity of sound in solid is more than that in liquid.why?
Velocity of sound travels faster in solids than in liquids, and faster in liquids than in gases because "the density of solids is higher than that of liquids, meaning that the particles are closer together."
Answer:
Explanation:
Due to the fact that sound is caused by vibrations, it's more noticeable in liquid because the vibrations may cause ripples in the liquid
Un avión da "una vuelta mortal" de radio R = 500 m con una celeridad constante v = 360 km/h. Halla la fuerza ejercida por el asiento sobre el piloto, si su masa es m = 70 kg, en las partes inferior y superior de la trayectoria circular.
Answer:
1400 N
Explanation:
Verá, durante el salto mortal, el piloto se mueve en una trayectoria circular y la fuerza que actúa sobre él es una fuerza centrípeta.
Sea la fuerza centrípeta F, la masa del piloto (m) = 70 Kg, el radio (r) = 500 my la velocidad (v) = 360 km / hr * 1000/3600 = 100 m / s
F = mv ^ 2 / r
F = 70 * (100) ^ 2/500
F = 1400 N
How does a wheel and axle make work easier?
The wheel and axle is a simple machine that reduces the friction involved in moving an object, making the object easier to transport. ... Once the object is moving, the force of friction opposes the force exerted on the object. The wheel and axle makes this easier by reducing the friction involved in moving an object.
In addition to reducing friction, a wheel and axle can also serve as a force multiplier, according to Science Quest from Wiley. If a wheel is attached to an axle, and a force is used to turn the wheel, the rotational force, or torque, on the axle is much greater than the force applied to the rim of the wheel.
A box weighs 1300 N. When a horizontal force of 390 N has applied the box accelerates at 1.3 m/s2. What is the magnitude of the frictional force?
Answer:
Ffriction = 217.7[N]
Explanation:
First, we must find the mass of the box, we must remember that the weight is defined as the product of the mass by acceleration.
[tex]w=m*g[/tex]
where:
w = weight [N] (units of Newtons)
m = mass [kg]
g = gravity acceleration = 9.81 [m/s²]
[tex]1300=m*9.81\\m=132.51[kg][/tex]
Now we must use Newton's second law, which tells us that the sum of forces is equal to the product of mass by acceleration.
∑F = m*a
where:
∑F sum of forces
m = mass = 132.51[kg]
a = acceleration = 1.3[m/s²]
We must know that the forces that act are the horizontal force that moves the box and the friction force in the negative direction that acts against the movement.
Now replacing:
[tex]390-f_{friction}=132.51*1.3\\390-172.26=f_{friction}\\f_{friction}=217.7[N][/tex]
If Minnie the Mouse starts moving at 2m/s and increases her velocity to 4m/s because she is being chased, what is heracceleration if the time is 2 seconds?
Answer:
1m/s²
Explanation:
Given parameters:
Initial velocity = 2m/s
Final velocity = 4m/s
Time of chase = 2s
Unknown:
Acceleration = ?
Solution:
Acceleration is the rate of change of velocity with time;
A = [tex]\frac{v - u }{t}[/tex]
A is the acceleration
v is the final velocity
u is the initial velocity
t is the time taken
A = [tex]\frac{4 - 2}{2}[/tex] = 1m/s²
1. How much heat must be absorbed by 375 grams of water to raise its
temperature by 25° C?(Cp of water is 4.184)
Answer:
39225J
Explanation:
Given parameters:
Mass of water = 375grams of water
Change in temperature = 25°C
Specific heat capacity of water = 4.184J/g°C
Unknown:
Amount of heat absorbed = ?
Solution:
To solve this problem, we use the expression below:
H = m c Ф
H is the heat absorbed
m is the mass
c is the specific heat capacity
Ф is the change in temperature
Insert the parameters and solve;
H = 375 x 4.184 x (25) = 39225J
a train has an initial velocity of 44m/s and an accelaration of _4m/s calculate its velocity
Answer:
It's 4m/s
Explanation:
V = u _ at, at u = 44m/s
44 + [-4]10
4m/s
What is your average speed if you walk 2 kilometers in 20minutes
Answer:
12 km/hr
Explanation:
Speed= Distance/Time
Answer:
12km/h
Explanation:
average speed= Distance covered /time taken
average speed=2km/20minutes
=but 1 minutes is 60 seconds
=2km/60minutes
=12km/h
Two billiard balls of equal mass collide. Ball 1 is initially moving at 0.43 m/s to the left, and ball 2 is initially at rest. Which of the following sets of final velocities does not describe an inelastic collision between the balls?
A. Ball 1 at 0.12 m/s left, Ball 2 at 0.31 m/s left
B. Ball 1 at 0.21 m/s left, Ball 2 at 0.22 m/s left
C. Ball 1 at 0.10 m/s left, ball 2 at 0.33 m/s left
D. Ball 1 at rest, ball 2 at 0.43 m/s left
Answer: B
"Ball 1 at 0.21 m/s left, Ball 2 at 0.22 m/s left"
how is velocity ratio of wheel and axle calculatedaad
Answer:
VR = [tex]\frac{Radius of wheel}{Radius of axle}[/tex]
Explanation:
A machine is a device that can be used to overcome a load by the application of an effort through a pivot. Examples are: pulleys, wedge, screw jack, wheel and axle etc.
The wheel and axle is a simple device that can be used to lift a load through a height. Its velocity ratio (VR) can be determined by:
VR = [tex]\frac{Radius of wheel}{Radius of axle}[/tex]
Note that for a practical wheel and axle, the radius of the wheel is greater than the radius of the axle.
.A water tank has dimensions
of 6m x 4m x 4m. Find the pressure exerted by
water at the base of dam when it is half
filled. ( Density of water - 1000 kg/ m2,
acceleration
due to to gravity is 9.8m/s2
Answer:
9800Nm⁻²
Explanation:
Given parameters:
Dimensions of the water tank = 6m x 4m x 4m
Density of water = 1000kgm⁻³
Gravity = 9.8m/s²
Unknown:
Pressure exerted by the water at the base of the dam = ?
Solution:
The pressure exerted by the water is given as:
Pressure = density of water x acceleration due to gravity x height of water
The height of the water here is half = 1m
Pressure = 1000 x 9.8 x 1 = 9800Nm⁻²
A 1.0-kilogram rubber ball traveling east at 4.0 meters per second hits a wall and bounces back toward the west at 2.0 meters per second. Compared to the kinetic energy of the ball before it hits the wall, the kinetic energy of the ball after it bounces off the wall is
Answer:
8 J and 2 J
Explanation:
Given that,
Mass of the rubber ball, m = 1 kg
Initial speed of the rubber ball, u = 4 m/s (in east)
Final speed of the rubber ball, v = -2 m/s (in west)
We need to find the kinetic energy of the ball before it hits the wall, the kinetic energy of the ball after it bounces off the wall.
Initial kinetic energy,
[tex]K_i=\dfrac{1}{2}mv^2\\\\K_i=\dfrac{1}{2}\times 1\times (4)^2\\\\K_i=8\ J[/tex]
Final kinetic energy,
[tex]K_f=\dfrac{1}{2}mv^2\\\\K_f=\dfrac{1}{2}\times 1\times (2)^2\\\\K_f=2\ J[/tex]
So, the initial kinetic energy is 8 J and the final kinetic energy is 2 J.
The kinetic energy of the ball after it bounces off the wall is 2.0 Joules.
The kinetic energy of an object is the energy that is in motion or performing work. It can be expressed by using the formula:
[tex]\mathbf{K.E = \dfrac{1}{2}mv^2}[/tex]
The mass of the object(rubber ball) = 1.0 kgThe initial speed of the rubber ball before the collision = 4.0 m/sThe final speed of the rubber ball after the collision = - 2.0 m/sThe Kinetic energy of the ball after the collision and when it bounces off the wall is computed as:
[tex]\mathbf{K.E = \dfrac{1}{2} \times 1 \times 2.0^2}[/tex]
K.E = 2.0 Joules
Learn more about kinetic energy here:
https://brainly.com/question/8101588
What is the volume of a liquid in a 50 mL cup?
A. 50mL
B. 10mL
C. There is not enough information to answer this question.
Answer:
there is not enough information
A plane flew at a speed of 600 km/hr for a distance of 1500 km,
How long did take to get to its destination
Explanation:
600 ÷ 60 = 10
1500 ÷ 10 = 150 minutes
I don't know how you should express the answer in:
So it's either 150 minutes or 2 hours and 30 minutes.
(This is kind of like mathematics, not physics)
asap plz help me
Which option identifies the importance of Snow’s scientific work to the medical community?
It was the foundation for epidemiology.
It pioneered the invention of vaccines.
It was the foundation for germ theory.
It created sterilization techniques.
Prior to germ theory, how were diseases thought to be transmitted?
human contact
animal contact
poisonous air
spoiled food
Answer:
It founded the foundation for epidemiology Human contactThe answer are:
1. It founded the foundation for epidemiology.2. poisonous airWhat nuclear reaction is shown in the equation below?
A. Nuclear fusion
B. Nuclear fission
C. Positron emission
D. Beta decay
The carbon isotope was cobined with the proton to produce the nitrogen isotope hence it is a fusion reaction.
What is a nuclear fusion?The term nuclear fusion refers to a kind of reaction in which two nuclei fuse together to give rise to a single nuclei with the evolution of energy.
We can see that the carbon isotope was cobined with the proton to produce the nitrogen isotope hence it is a fusion reaction.
Learn more about nuclear fusion:https://brainly.com/question/12701636
#SPJ2
Answer:
A. Nuclear fusion
Explanation:
got it right, trust
Help !!!!!!!!
Please its Urgent.
None can.
A clinical thermometer only measures temperatures above +30°C.
Mercury and alcohol are both frozen solid at -50°C.
I need the answers ASAP.
Answer:
Explanation:
A) Large: As she opens her parachute, she begins to displace a large volume of air. This leads to a Large air resistance
B) increase, weight: As she falls, the air resistance force increases. Now there is a force acting in opposite directions to her weight.
C)Weight, Decelerate: The skydiver has only the downward force of her weight pulling down on her, so she starts to decelerate
D) Weight, Upward, Resultant:
Her weight is now equal to the upward force from the ground. Her resultant force is then zero
E) Increases, same, constant, resultant, terminal:
As she accelerates faster, the air resistance force increases. It is now the same as her weight. She now moves at a constant speed because the resultant force acting on her is zero. She is now at her terminal velocity.
F) Increases, same, constant, terminal:
As she decelerates, the air resistance force on her parachute increases until it is the same as her weight. She is now moving with a constant speed until she hits the ground - a new slower terminal velocity
Who is the father of Nuclear Physics?
Answer:
Ernest Rutherford, 1st Baron Rutherford of Nelson
Can someone please help? Please?
Answer:
I think A= 5M/S is answer
A lift travelling up to the top floor of the Empire State building with a mass of 4200kg and a kinetic energy of 4116J. Find the velocity
Answer:
1.4 m/sExplanation:
The velocity can be found by using the formula
[tex]v = \sqrt{ \frac{2k}{m} } \\ [/tex]
k is the kinetic energy
m is the mass
From the question we have
[tex]v = \sqrt{ \frac{2 \times 4116}{4200} } \\ = 1.4[/tex]
We have the final answer as
1.4 m/sHope this helps you
Answer:
The speed of the lift is 1.4 m/s
Explanation:
Kinetic Energy
Is the type of energy of an object due to its motion. It's proportional to the square of the speed and the mass.
The equation for the kinetic energy is:
[tex]\displaystyle K=\frac{1}{2}mv^2[/tex]
Where:
m = mass of the object
v = speed at which the object moves
The kinetic energy is expressed in Joules (J)
It's given the mass of the lift as m=4,200 kg and its kinetic energy K=4,116 J. To calculate the speed (magnitude of velocity), we solve the formula for v as follows:
[tex]\displaystyle v=\sqrt{\frac{2k}{m}}[/tex]
[tex]\displaystyle v=\sqrt{\frac{2*4,116}{4,200}}[/tex]
[tex]\displaystyle v=\sqrt{1.96}[/tex]
v = 1.4 m/s
The speed of the lift is 1.4 m/s
find the cp of an article which is sold for rupees 4048 , thereby , making a profit of 15 percent
Answer:
4048 = 115x/100.
Explanation:
Profit P = (15/100) X x.
P= 15x/100.
15x/100 = 4048- x.
4048 = 15x/100 + x.
4048 = 115x/100.
Sound is repeated near hills.why
Answer:
Sound waves are reflected back
The PE of the box that is on a 2.0 m high self is 1600 J. What is the power expelled to lift the box to this height in 10.0 seconds?
Answer:
160 W
Explanation:
Power is the ratio of work to time:
(1600 J)/(10 s) = 160 J/s = 160 W
What 2 factors impact gravitational pull?
mass and distance
matter and energy
size and shape
speed and direction
Answer:
When dealing with the force of gravity between two objects, there are only two things that are important – mass, and distance. The force of gravity depends directly upon the masses of the two objects, and inversely on the square of the distance between them
Bob the Builder is making a delivery of wood in his work truck. He is traveling at the velocity of 12 mi/hour at the top of the hill. Nine seconds later he reaches the bottom of the hill and is moving north at 25 mi/hour. What is the acceleration?
Answer:
Acceleration, a = 0.65m/s² due North.
Explanation:
Given the following data;
Initial velocity = 12mi/hr
Final velocity = 25mi/hr
Time = 9 secs
To find the acceleration;
First of all, we would convert miles per hour to meters per seconds.
[tex] Initial \; velocity = \frac {12 * 1609.344}{60*60} = \frac {19312.128}{3600} = 5.37m/s [/tex]
[tex] Final \; velocity = \frac {25 * 1609.344}{60*60} = \frac {40233.6}{3600} = 11.18m/s [/tex]
Now to find the acceleration;
Mathematically, acceleration is given by the equation;
[tex]Acceleration (a) = \frac{final \; velocity - initial \; velocity}{time}[/tex]
Substituting into the equation, we have;
[tex]a = \frac{11.18 - 5.37}{9}[/tex]
[tex]a = \frac{5.81}{9}[/tex]
Acceleration, a = 0.65m/s² due North.