A roller coaster car starts stationary at the top of a downwards slope. At the bottom of the slope, it has a speed of 30m/s. Use the conservation of energy to find the vertical height of the slope. (Use g=10 m/s^2)
From the conservation of energy, we know that the change in gravitational potential energy (GPE) is equal to the change in kinetic energy (KE). GPE=mgh and KE=(1/2)mv^2. At the top of the slope, the car starts stationary so has KE=0 and at the bottom of the slope GPE=0. Therefore the GPE at the top equals the KE at the bottom. mgh=(1/2)mv^2. Divide both sides by the mass (m) to get gh=(1/2)v^2 and rearrange to find h, h=v^2/2g. Substitute in the numbers to find h=45m (don't forget units!)
TM
Related Physics GCSE answers
All answers ▸A sequence is defined by the recurrence relation u(n+1) = 1/3 u(n) + 10 with u(3) = 6 . Find the value of u(4) and the limit of the sequence.
A person swims from a depth of 0.50 m to a depth of 1.70 m below the surface of the sea. Density of the sea water = 1030 kg/m^3. Gravitational field strength = 9.8 N/kg. Calculate the increase in pressure on the swimmer. Give the unit.
What led to the Plum Pudding model being replaced by Rutherford's nuclear model of the atom? (6 marks)
A car of mass 1000 kg is travelling at 20 (m/s). The car crashes into a tree, and comes to a complete halt in 0.05s. Calculate the force acting on the car during the collision.