**q3 ****Answers**

**Questions**

(1)

**Figure 1**shows part of a roller coaster ride seen from the side.

(a) The roller coaster car rolls down towards

Which of these is the correct equation for calculating the kinetic energy of the car? (1)

**P**. The car has mass,*m*kg and velocity*v*m/s.Which of these is the correct equation for calculating the kinetic energy of the car? (1)

(b) The mass of the car is 580kg.

The car gains 39000J of gravitational potential energy as it climbs from

(i) State the equation relating change in gravitational potential energy, mass, gravitational field strength and change in vertical height. (1)

(ii) Calculate the height

The car gains 39000J of gravitational potential energy as it climbs from

**P**to**Q**.(i) State the equation relating change in gravitational potential energy, mass, gravitational field strength and change in vertical height. (1)

(ii) Calculate the height

*h*, shown in Figure 1. (gravitational field strength,*g*= 10N/kg) (3)

*h*= ............................................... m

(c) The car enters a pool of water at

Describe how the total energy of the system is conserved as the car travels between

**R**. It slows down and stops at**S**.Describe how the total energy of the system is conserved as the car travels between

**R**and**S**. (2)**(Total for Question 1 = 7 marks)**