Work is required to lift a barbell. How many times more work is required to lift the barbell 2 times as high

I assume you mean an angle of θ, and not 0. I also assume the given components of the initial velocity are horizontal and vertical, respectively, so that

1. the initial velocity vector is

[tex]\boxed{\vec v_i = (7.5\,\vec\imath + 13\,\vec\jmath) \dfrac{\rm m}{\rm s}}[/tex]

which means the ball is thrown with an initial speed of

√((7.5 m/s)² + (13 m/s)²) ≈ 15 m/s,

and

2. the angle made by [tex]\vec v_i[/tex] with the positive horizontal axis is θ such that

[tex]\tan(\theta) = \dfrac{13}{7.5} \implies \theta \approx \arctan(1.7) \approx \boxed{60^\circ}[/tex]

3. At time t, the ball attains a height y and horizontal range x according to

y = (13 m/s) t - g/2 t²

x = (7.5 m/s) t

where g = 9.8 m/s². When the ball reaches the ground (y = 0) for t > 0, we have

(13 m/s) t - g/2 t² = 0

13 m/s - g/2 t = 0

t = 2 (13 m/s)/g = (26 m/s)/g

Plugging this time into the x equation gives a horizontal range of

x = (7.5 m/s) (26 m/s)/g ≈ 20. m

In trajectory, acceleration vector is not the same with the velocity vector but it depends on the change in velocity. The acceleration path is perpendicular to the velocity vector path. The Correct answers are:

a.) D

b.) B

c.) C

d.) A

A Vector is a quantity that has both magnitude and direction.

Given that a  ball is fired from a cannon at point 1 and follows the trajectory shown in the figure.

a.) The vector best represents the ball's velocity at position 2 is D

b.) The vector best represents the ball's acceleration at point 2 is B

c.) Which vector best represents the ball's velocity at position 3 = C

d.) Which vector best represents the ball's acceleration at point  = A

In trajectory, acceleration vector is not the same with the velocity vector but depends on the change in velocity. The acceleration path is perpendicular to the velocity vector path.

At point 3, since the ball path is parabolic, the velocity at that point is not equal to zero but will tend to take a horizontal path.

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Trick to identify:-

Answer:

In an exothermic reaction, energy is

✔ released to

 the surroundings.

In an endothermic reaction, energy is

✔ absorbed from

 the surroundings.

Explanation:

[tex]1~N = 1~ \text{kg~ms}{^{-2}[/tex]

1 N = 1 kg × m/s²

One Newton is equal to 1 kilogram multiplied by meter by second squared.

_____

Hope it helps ⚜

Answer:

a. specific heat

Explanation:

a. specific heat

Answer:

hen dealing with the force of gravity between two objects, there are only two things that are important – mass, and distance.

Explanation:

Speed= 60 m/s

for converting m/s to km/h =multiply with 5/18

for converting km/h to m/s= multiply with 18/5

so, 60 × ( 18/50) = 216 km/h

Answer:

hi I don't know sorry sorry forgive me

Explanation:

sorry

Answer:

6500N

Explanation:

F = ma so therefore Were given mass (m) = 1500 kg, acceleration (a) = 5 m/s2, well have to calculate the force to be:

1500 x 5 = 6500 N

Answer:

B. between carbon and oxygen

Explanation:

formaldehyde has a carbon atom that has single bonds with two hydrogen atoms on both sides, and it has a double bond with oxygen.

Answer:

The placement of the double bond is between carbon atom and oxygen atom

this same question was for me so I did and got it correct

please mark me as brainliest

Answer:

C

Explanation:

The natural light display called aurora borealis is located in the northern

hemisphere.

There are two types of aurora which are called aurora borealis and aurora

australis. The aurora borealis is located in the Northern hemisphere while

the aurora australis is located in the Southern hemisphere.

They receive their energy through the interaction of charged particles

on the Sun and Earth to produce the light display. An example

of the interaction involves solar wind with atoms of the upper atmosphere.

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Answer:

northern and southern hemisphere

Explanation:

Answer:

e

Explanation:

It is possible to create a wave having some frequency on a rope and then gradually it will become faster. During this time wavelength becomes shorter. Here the wave 'e' is found to has highest frequency. The correct option is E.

The number of oscillations of a wave per unit time is defined as the frequency. It is usually measured in Hertz and the frequency is directly proportional to the pitch. Humans can hear sounds with frequencies ranging between 20-20000 Hz.

The sounds with frequencies over the human ears range are called the ultrasonic sound and sounds with frequencies less than the audible range are called infrasonic sound. The wavelength and frequency are inversely proportional to each other.

When wavelength increases, frequency decreases and vice versa. So here wave E has maximum number of vibrations.

Thus the correct option is E.

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Answer:

carbon dioxide (what you are blowing up the balloon with) is a heavy gas. so when you fill the Balloon with it, the balloon will not float. helium is a light gas and floats. gravity takes another. part in this

Answer:41xm/s

Explanation:

Answer:41xm/s

Explanation:

I found this for you hope it helps.

Answer:

A.

Explanation:

Thats my answer

Please make me branlies answer

Answer:

density

Explanation:

because it is directly proportional

Pressure in a liquid depends on the density of the liquid.

Density is defined as the mass per unit volume. It is an important parameter to understand the fluid and its properties. Its unit is kg/m³.

The pressure in the liquid is;

P = ρgh

Where,

h is the height

ρ is the density

g is the acceleration due to gravity

The density of a liquid determines its pressure.

Hence, density is the correct answer.

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Answer:

50J

Explanation:

Ep = mgh

Here,

m = 1kg; g = 10 m/s2; h = 5m

So, Ep = 1kg*10m/s2*5m

= 50J

So, the potential energy is 50J (Ans).

Answer:

25mg

Explanation:

it basically explains itself

Explanation:

Initial horizontal velocity

If a projectile is launched at an angle to the horizontal, then the initial velocity of the projectile has both a horizontal and a vertical component. The horizontal velocity component (vx) describes the influence of the velocity in displacing the projectile horizontally.

The initial horizontal velocity can also be determined by measuring the diameter d of the ball and dividing by the time t that it takes for the ball to move across the photogate. That is Vo = d/t.

Initial vertical velocity

Vertical velocity refers to the speed of an object's movement in a vertical direction.The initial vertical velocity is the vertical component of the initial velocity: v 0 y = v 0 sin θ 0 = ( 30.0 m / s ) sin 45 ° = 21.2 m / s .

Answer:

Definition of spectral line: one of a series of linear images formed by a spectrograph or similar instrument and corresponding to a narrow portion of the spectrum of the radiation emitted or absorbed by a particular source.

Definition of Wavelength: can be defined as the distance between two successive crests or troughs of a wave. It is measured in the direction of the wave. ... Wavelength is inversely proportional to frequency. This means the longer the wavelength, lower the frequency.

So, the spectrum is the range of wavelength in visible light. While, wavelength is the length of a wave.

Explanation:

I hope this helps!

Answer:

the acceleration of the rocket is: a=vemΔmΔt−g a = v e m Δ m Δ t − g .

Explanation:

I answered this before.

hope this helps! :)

Answer:

Node-Antinode       for a pipe closed at one end (fundamental)

The length of such a pipe would be wavelength / 4

lambda (wavelength) = speed / frequency = 344 m/s / 63 / sec = 5.46 m

The pipe would have to be 5.46 / 4 = 1.36 m

Answer:

24mm

Explanation:

3 N to g is 305.9 g

50g ---- 4 mm

305.9 ----- 4×305.9/50 = 24 mm