Superman must stop a 160-km/h train in 180 m to keep it from hitting a stalled car on the tracks. Part A
If the train's mass is 3.8×105 kg , how much force must he exert (find the magnitude)?
Express your answer using two significant figures.
Part B
Compare to the weight of the train (give as %).
Express your answer using two significant figures.
Part C
How much force(in magnitude) does the train exert on Superman?
Express your answer using two significant figures.

Determine the amount of work done when a crane lifts a 100-n block form 2m above the ground to 6m above the ground

Match these items. 1. coulombs __force 2. ohms __emf 3. centimeters __resistance 4. newtons __charge 5. volts __length

An charge with mass m and charge q is emitted from the origin, (x,y)=(0,0). a large, flat screen is located at x=l. there is a target on the screen at y position y(h), where y(h) > 0. in this problem, you will examine two different ways that the charge might hit the target. ignore gravity in this problem. 1.assume that the charge is emitted with velocity v(0) in the positive x direction. between the origin and the screen, the charge travels through a constant electric field pointing in the positive y direction. what should the magnitude e of the electric field be if the charge is to hit the target on the screen? express your answer in terms of m, q, y(h), v(0), and l. 2.now assume that the charge is emitted with velocity v(0) in the positive y direction. between the origin and the screen, the charge travels through a constant electric field pointing in the positive x direction. what should the magnitude e of the electric field be if the charge is to hit the target on the screen? express your answer in terms of m, q, y(h), v(0), and l.