Work Energy Power

Work Energy Power

By Huang Zhijie

​Work done can be defined as the energy gained by the object.

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W = F x D​

Open Ended

Vishnu lifted a 2.0 kg dumbbell up 0.75 m. What is the work done by Vishnu?

Open Ended

Jun Rong pushed against a 500 kg rock. The rock did not move. What is the work done by Jun Rong

Kinetic Energy - The energy of movement Pg(112)

Open Ended

Javier sleep walks at 0.5 m/s. He has a mass of 50 kg. What is his kinetic energy?

Open Ended

Chin Ru kicks a ball. The ball rolls away at a speed of 3.2 m/s. What is the work done by Chin Ru on the ball?

​Gravitational Potential Energy

​An object have gravitational potential energy (GPE) due to its position above the ground. The higher it goes, the more GPE it has.

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E = mgh​

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Gain in GPE can be defined as work done against gravity.​

Open Ended

Zhan Yu climbs a 5.0 m flight of stairs. Given that he is 50 kg, what is the gain in GPE?

Open Ended

Zhan Yu climbs a 5.0 m flight of stairs. Given that he is 50 kg, what is the work done by Zhan Yu against gravity?

Open Ended

A 0.5 kg ball is released from a 10 m tall building. What is the kinetic energy of the ball just before it hits the ground?

Open Ended

Velan throws a ball 0.5 kg ball upwards. Given that the ball has an initial speed of 3.0 m/s, what is the GPE of the ball at the top? What is the height that the ball will reach?

Open Ended

A 100 kg wild boar slips and rolled down from a 3.0 m smooth slope. What is the kinetic energy of the wild boar at the bottom of the slope?

Open Ended

A 100 kg wild boar slips and rolled down from a 3.0 m smooth slope.

The wild boar hits a sleeping, stationary 40 kg Xavier at the bottom of the slope.

Xavier starts rolling on the smooth road and stops 2 m away. What is the impact force on Xavier by wild boar?