Physics a 2019 unit 4 test the unit 4 test for physics a
in the picture below, the block is being hung in equilibrium. what is the tension needed in each of the ropes to keep the box in equilibrium? ignore all friction and show all work (3 points)

a broken leg is kept in traction in the medical device pictured below. the device is designed to use the ropes to provide a constant horizontal force of 30 n on the leg. what must the weight of block a be for this horizontal force? ignore all friction and show all work (3 points)

a spring scale is pictured below measuring two weights at the same time. each weight is identical. ignoring all friction, what will the spring scale read as the total weight? (1 point)
0 n
50 n
100 n
impossible to tell

a person is pulling their 20 kg luggage using the luggage handle. the handle is at an angle of 56 degrees above the horizontal. if the person is pulling with a force of 71 n, what is the horizontal acceleration of the luggage (ignore all friction) (1 point) 3.19 m/s^2
1.99 m/s^2
0.74 m/s^2
1.02 m/s^2
a train is pulling four train cars and each car has a mass of 40,000 kg. the train is accelerating at 1.1 m/s^2. what is the force produced by the train's engine car to provide this acceleration? (ignore all friction) (1 point)
211000 n
149000 n
201000 n
176,000 n

in the picture below, the 21 kg mass is attached by a cord to a mass hanging over the edge of the table. the frictional force between the mass and the table's surface is 121 n. the mass accelerates at a rate of 0.73 m/s^2 to the right. what is the weight of the hanging block? show all work (3 points)

a washing machine sits on the floor. how can you increase the force of friction on the washing machine without changing the surfaces of the floor or washing machine? explain your reasoning (2 points)

a 3000 kg truck is sliding down a hill that is at an angle of 40 degrees above the horizontal. if the coefficient of friction between the truck and the hill is 0.2, what is the acceleration of the truck? ignore all other forms of friction. show all work (3 points)

a spring is compressed by 15 cm when 400 n of force is applied. what is the spring constant of the spring? (1 point) 3491.4 n/m
2666.7 n/m
1892.9 n/m
2877.1 n/m

a student measures the force required to stretch a spring a certain distance and produces a graph of distance vs force, pictured below. if the spring being measured obey's hooke's law, how much force will be needed to stretch the spring 17 cm? (1 point)
25.5 n
21.2 n
33.9 n
18.3 n