1. The small rocket engines used in model rockets are rated by the impulse they exert on the rocket. The graph below shows the force exerted by an engine during the 1.0 second from when it is ignited until when the fuel is completely bumed. a) What is the impulse of this rocket engine? F(N) 0.2 0.4 0.6 0.8 1.0 b) One of these engines is put horizontally on a frictionless cart of mass 780 g so that it will accelerate the cart. How fast will the cart be going after the engine has burned all of its fuel? The mass of the engine itself is small enough that we can ignore it.

Problem 1 The crate has a weight of 100 lb and is initially at rest. The force P is sufficient for the crate to move down the incline at a velocity of 5t. The coefficient of kinetic friction μk = 0.25. a) Draw a complete Free Body Diagram. b) Write the equations of motion for your selected coordinates. The only variables should be unknowns. c) Solve for the required force P. d) What is the velocity when the crate has traveled one foot. 30° P

Q1(A) At a carnival, a daredevil rides a motorcycle around and around the "wall of death," a wooden cylinder with vertical walls. The radius of the cylinder is R = 5.0m, and the coefficient of static friction between the motorcycle's tires and the walls is us = 0.90. a) Draw a force diagram for the motorcycle. b) What is the minimum speed at which the motorcycle can ride in a horizontal circle without sliding down to the bottom? Q1(B) An elevator and its load have a combined mass of 1100kg, and is suspended from a strong metal cable. The elevator is initially moving upward at 7.00m/s; it slows to a stop with a constant acceleration in a distance of 20.0m. What is the tension T in the elevator cable during this process?

2 Your friend is planning to ride his bike up a ramp and land on the roof of a building as shown below. The building is 6.00 m high and 8.00 m away from the ramp. The ramp is 3.00 m wide and 4.00 m tall. 4.00 m 1 ← 3.00 m 6.00 m 8.00 m A. What is the minimum speed with which your friend needs to leave the ramp in order to land on the building? B. Another friend is going to use his motorized scooter for the same stunt. The maximum speed of the scooter is 15.0 m/s. How close to the building should you move the ramp so that your friend lands on the roof right at the front edge of the building?

A mover lowers a piano weighing 200.0 kg using the pulley system in the diagram below. Assume that the piano is initially 2 m from the ground. a) How much work does the mover have to do to slow down the piano's descent if it reaches a speed of 0.25 m/s at 1 m from the ground? b) Assuming that the mover exerts a constant force what is the modulus of this force? c) Deduce the piano's acceleration.

a) Calculate the direction in degrees of the final velocity of the bowling ball, relative to its initial direction of travel. b) calculate the magnitude of the final velocity, in meters per second, of the bowling ball.

Q1) A stationary nozzle produce a water jet and the jet strikes an axisymmetric plate as shown. The plate is attached to a piston-cylinder system. The discharge is 2.5 L/s and all other data are listed in the given table. a) Determine the pressure inside the nozzle p. b) Determine the pressure inside the cylinder at equilibrium p. c) Suggest a way for increasing the pressure inside the cylinder to the maximum amount without changing the nozzle properties. d) Calculate the maximum pressure inside the cylinder according to your suggestion in part (c). dz P, =? P=? d¡ 75 mm d2 12 mm D 50 mm 0 10° Flow Fixed Platform

The vehicle shown starts from rest at the bottom of the hill and accelerates up the hill due to the force FR from the road. Note that this is a static friction force and is not dissipative. Vrop = 9.7 m/s m = 1600 kg h = 50 m FR = 7300 N 0 = 25° A) If the vehicle reaches the top of the hill with the speed shown, how much thermal energy is dissipated in the process? B) Assuming that air drag, Fang , is the only dissipative force during this process, try to estimate the cross-sectional area of the vehicle "seen" by the air. In the formula for air drag, regard the car's speed as being a constant v = 5.0 m/s (this speed is roughly half of the starting and ending speeds). Use C = 0.5 for the drag coefficient and p = 1.25 kg/m³ for air density.

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A free hanging system of 5 kg weight, and 6 kg weight, tied together with a 4 kg rope is pulled upwards with a force of 300 N. A) what is the acceleration of the system? B) what is the tension of the system? C) what is the tension from the middle of the rope ?