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3 years ago

Kinetic Energy RE-

Physics

1 answer:

tatiyna3 years ago

8 0

Answer:

1) The potential energy, P.E = 4527.6 J

2) The mass, m = 1.28 kg

3) The height of the bell, h = 4.31 m

4) The kinetic energy, K.E = 385 J

5) The velocity of the car, V = 22.53 m/s

6) The mass of the car, m = 17.59 kg

Explanation:

1) The height of the hill, h = 21 m

The carriage with a baby has mass of, m = 22 kg

The potential energy,

P.E = mgh

= 22 x 9.8 x 21

= 4527.6 J

2) The height of the platform, h = 20 m

The P.E of the cinder block, P.E = 250 J

The mass,

m = P.E / gh

= 250 / (9.8 x 20)

= 1.28 kg

3) The mass of the bell, m = 18 kg

The P.E of the bell, P.E = 760 J

The height of the bell,

h = P.E/mg

= 760 / 18 x 9.8

= 4.31 m

4) The mass of the runner, m = 55 kg

The velocity of the runner, v = 14 m/s

The kinetic energy,

K.E = ½ mv²

= ½ x 55 x 14

= 385 J

5)The kinetic energy of the car, K.E = 69,759 J

The mass of the car, m = 275 kg

The velocity of the car,

V = √(2K.E/m)

V = √( 2 x 69759 / 275)

= 22.53 m/s

6) The velocity of the car, v = 38 m/s

The kinetic energy of the car, K.E = 12700 J

The mass of the car,

m = 2 K.E/ v²

= 2 x 12700 / 38²

m = 17.59 kg

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From the question we are told that

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