QUESTION 1
A car of mass 800 kg is pulling a trailer of mass 300 kg up the slope of angle ? to the horizontal where sine ? = 1/200. Resistance to motion (apart from gravity) is 1.5 N per kg of mass for each vehicle. Calculate the pull of the engine and the tension in the tow -bar when they are:
(a) Moving with constant velocity,
(b) Accelerating at 0.2m/s2
QUESTION 2
(a) A pump raises water through a height of 15m at the rate of 0.05m3 per second. What is the power of the pump?
(b) A constant force acts on a body of mass 2kg and does 45j of work. The effect on the body is that its final velocity is 2m/s more than its initial velocity. Find the initial velocity of the body.
QUESTION 3
(a) A hose (cross-section 4cm2 ) delivers water horizontally with a speed of 25m/s. What is the impulse of the water on a vertical wall (assuming no rebounds)? What average force acts on the wall?
(b) Two masses of 30kg and 20kg, traveling at 4m/s and 1m/s respectively in the same direction, collide and continue together. Find their common speed after the collision?
QUESTION 4
(a) A 600 kg satellite is in circular orbit about Earth at a height above Earth equal to Earth‘s mean radius. Find:
(i) The satellite’s orbital speed,
(ii) The period of its revolution ,
(iii) The gravitational force acting on it.
(b) A 50g mass moves as a conical pendulum with string length 9 x and speed v. if the radius of the circular motion is 7 x find:
(i) The string tension (answer to 2 d .p.),
(ii) V in terms of x, g.