Question

1. A stunt performer (m=60 kg) is launched from a cannon (safely). Inside the cannon the performer is launched straight up in the air, from rest to a speed of 30 m/s through an 8 m long cannon. a) (2 pts) How much energy is required to launch the performer? b) (2 pts) How much force is required to launch the performer? c) (4 pts) What is the performer's speed when they are 10 m above the ground? 2. An object is pulled at a constant velocity 4 m at an angle of 25 south of east by a force of magnitude 280 N applied an angle of 42° degrees south of east. a) (1 pts) Write the force using vector notation. b) (1 pts) Write the displacement using vector notation. c) (2 pts) Find work done by the pulling force using W = |F||d| cose. d) (2 pts) Find the work done by the pulling force using the doc product definition of work. e) (2 pts) What is the net work done on the box? 3. While moving out of your apartment, you need to lift a heavy box of textbooks a height h into the back of a truck. You can either lift the box straight up or slide the box up a ramp of length L to load the box (see image below). show (box is lifted straight up) (box is slid up a ramp) I Work blz Assume the ramp is frictionless. a) (3 pts) Which scenario requires you, the lifter, to do more work on the box to load it into the truck? Explain using relevant physics concepts and terminology. b) (3 pts) In which scenario is the magnitude of work done by gravity on the box the greatest? Explain using relevant physics concepts and terminology. c) (3 pts) If friction does exist between the ramp and the box, how would your answers to parts a) and b) change? Explain using relevant physics terminology and concepts and terminology. 4. A child sleds down a hill 6 m height with an inclination of 10°. The child was given a velocity of 1 m/s at the top of the hill. The child and sled have a combined mass of 25 kg. At the bottom of the hill (point x) the sled has a velocity of 7 m/s. a) (3 pts) How much work was done by friction on the way down the hill? b) (3 pts) What is the force of friction on the sled? c) (3 pts) Assume the same frictional force exists on the flat ground at the bottom of the hill. How far will the sled travel until it stops? d) (2 pts) If the hill was frictionless, what would the sled's velocity be at the bottom (point x) of the hill? 6 m 10

Answer 1

a) E-t mu? {x60xb0)'> 290005 D W-FS Food and hope 39.25N. v2_ce? - zas v= as = /2x9.88103 140 Scanned with CamScanner