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4 years ago

Calculate the KE of a 3.1 kg toy cart that moves at 4.8 m/s. Calculate the KE of the same cart at twice the speed.

Physics

1 answer:

lisov135 [29]4 years ago

4 0

When v= 4.8 m/s:

E.K=mv²/2
=3,1(4.8)²/2
=35.712J

when v= 2(4.8):

E.K=mv²/2
=3.1(9.6)²/2
=142.848J

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Which of the following is not true about arid deserts?

andrezito [222]

Answer:

The answer is actually b

Explanation:

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3 years ago

When bridges are built, special joints must be used because the material of the bridge shrinks, and without these joints, the ma

egoroff_w [7]

Answer:

Option D.

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The correct answer is Option D.

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4 years ago

A 100-kg running back runs at 5 m/s into a stationary linebacker. It takes 0.5 s for the running back to be completely stopped.

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Answer:

1000 N

Explanation:

First, we need to find the deceleration of the running back, which is given by:

$a=\frac{v-u}{t}$

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t = 0.5 s is the time taken

Substituting, we have

$a=\frac{0-5 m/s}{0.5 s}=-10 m/s^2$

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6 0

3 years ago

Read 2 more answers

A pendulum consists of a 0.3 kg mass at the end of a string. The pendulum is raised to a height of 0.26 m and released. When the

Debora [2.8K]

The total energy of the Pendulum-Earth system is equal to 1.54416 Joules.

<u>Given the following data:</u>

Mass = 0.3 kg

Height = 0.26 meter.

Velocity = 2.28 m/s.

<u>Scientific data:</u>

Acceleration due to gravity on Earth = 9.8 $m/s^2$

To calculate the total energy of the Pendulum-Earth system:

<h3>How to calculate total energy.</h3>

The total energy possessed by this Pendulum-Earth system is equal to the sum of both the potential energy and kinetic energy at its lowest point.

Mathematically, the total energy is given by this formula:

$E = mgh + \frac{1}{2} mv^2$