(π) The passenger was right in saying so according to the laws of physics. Since the direction of force is vertically up and displacement horizontal, no work is said to be done.
(ππ) Sympathy and value for other’s work.
(πππ) When you push a heavy boulder but are unable to displace it.

(i) Calculate the kinetic energy of the car. (ii) Calculate the energy used in 1.0 s against the resistive force. (iii) What is the minimum power that the car engine has to deliver to the wheels? (iv) What form of energy is in the fuel, used by the engine to drive the car?