Q1. A weightlifter in a gymnasium raises a dumbbell of mass 16 kg through a height of 2 m from the ground to just above his head. How much gravitational potential energy has the dumbbell gained? Take the gravitational field strength to be in 9.81 N per kilogram.


Q2. An engineer takes his box of tools from the back of his van in the car park of a tower block to the roof space at the top in order to carry out some repair work. The engineers toolbox has a mass of 35 kg. Taking the gravitational field strength as 9.81 N per kilogram, approximately how tall is the tower block given that the toolbox holds 60,086.25 J of energy in its gravitational potential energy store when the engineer reaches the roof, and taking the gravitational field strength to be 9.81 N per kilogram?


Q3. The engineer in the previous question is quite reckless, and during his repairs at the top of the block of flats he accidentally drops a large spanner of mass 800 g from his work area and it falls to the ground. Given the gravitational field strength of 9.81 N per kilogram, at what speed do you think the spanner would hit the ground?


Q4. A driver for the local parcel delivery service has a mass of 110 kg. Carrying a 15 kg box he walks up six flights of stairs to the sixth floor of a tower block approximately 60 m. Calculate the change in gravitational potential energy of the box assuming that it is carried at a height of 1 m from the ground.


Q5. A 25,000 kg space vehicle takes off from a planet and climbs to a height of 12,000 m ready to dock with the mother ship. At the 12,000 m point the space vehicle has 2 940 000 000 J of energy in its gravitational potential energy store.Calculate the gravitational field strength in newtons per kilogram of the planet.


Q6. An astronaut, stands on the edge of a 455-metre cliff situated at the edge of a crater on Mars. Given that the mass of the astronaut plus all of his equipment is 110 kg, what is the value of the acceleration due to gravity on Mars if his GPE is 185185J?


Q7. A small test rocket with a mass of 250 kg blasts off from a launchpad. At a height of 300 m a parachute is deployed and the rocket returns safely to earth. What is the gravitational potential energy of the rocket at its highest point just before the parachute is deployed? Take the acceleration due to gravity as 9.81 m/s/s.


Q8. A space exploration lands on a distant planet with a gravity similar to that of Jupiter. A 50Kg boulder stands at the top of a sheer drop into a crater. Scientific instrumentation detects the boulder falling and crashing at the base of the crater, hitting the ground at 175 m/s. Taking the acceleration due to gravity on this planet as 26.49 m/s/s calculate the height of the drop into the crater.


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