6. Two automobiles collide at an intersection. One car of mass 1.4x10' kg is travelling at 45 km/h [S]; the other car of mass 1.3x10" kg is travelling at 39 km/h [E]. If the cars have a completely inelastic collision, what is their velocity just after the collision? a) 30 km/h b) 35 km/h c) 40 km/h d) 45 km/h 7. The magnitude of the total gravitational field strength at a point in interstellar space is 5.4x10 N/kg. What is the magnitude of the gravitational force at this point on an object of mass 1.00 kg a) 5.0x 10 N b) 5.2x 10 N c) 5.4x10 N d) 5.6x10 N 8. What is the change in gravitational potential energy of a 64.5-kg astronaut, lifted from Earth's surface into a circular orbit of altitude 4.4x10 km a) 2.0x 10' J b) 2.2 x 10' J c) 2.4 x 108 J d) 2.6x108 J 9. A hockey player passes a puck with an average force of 250 N. The hockey stick is in contact with the puck for 0.0030 s, and the mass of the puck is 180 g. The puck is not moving before the player passes it. T/I A (a) Determine the impulse imparted by the hockey stick a) 0.75 kg.m/s b) 0.76 kg.m/s c) 0.77 kg.m/s d) 0.78 kg.m/s 10. What is the total energy needed to place a 2.0x10" -kg satellite into circular Earth orbit at an altitude of 5.0x10 km? a) 6.7x10" J b) 6.8x 10" c 6.9x10" J d) 7.0x10" J