Mechanics | Relativity Answers

A car weighing 1000kg and travelling at 30m/s stops at a distance of 50m decelerating uniformly. What is the force exerted by the brakes and what is the work done by the brakes?

An optical grating with 5000 line 51cm gives a second order iamge. Ata diffraction angle 44.8 degree calculate the wave. Lenght of the light used

A particle travels to the right at a constant
rate of 8.8 m/s. It suddenly is given a vertical
acceleration of 2.6 m/s2
for 3.8 s.
What is its direction of travel after the
acceleration with respect to the horizontal?
Answer between
−180◦
and +180◦ .
Answer in units
of◦
008 (part 2 of 2) 10.0 points
What is the speed at this time?
Answer in units of m/s
PS:I need this no later than 11/19/12 at 9:00p.m and i already did the first part.

two trains move on parallel tracks in opposite directions away from each other. one moves at the rate of 50m/s, while the other moves at 70m/s. what is the magnitude of the velocity of each train relative to the other?

you walk away from an intersection at the rate of 1.1m/s for 60s. then you suddenly reverse course and run toward the intersection at the rate of 6.0m/s. formulate a d-t equation for each part of your trip.

A roller coaster is traveling at 5 m/s at the top of a hill 40 m above the ground. What is the speed of the roller coaster when it is 15 m above the ground?

A 20 kg box is initially sliding across the floor at 10 m/s. If the force of friction on the box is 50 N, how far will the box slide before coming to a stop?

A 30,000 kg railroad car initially traveling to the right at 15 m/s collides inelastically with a 20,000 kg railroad car initially traveling to the left at 5 m/s. The cars stick together. What is their final speed?

The graph shown describes a certain force that is exerted on an object, as a function of the position of the object. How much work is done by this force as the object moves from the position 0.0 m to 6.0 m?

If my best value for acceleration was 874 and it has to be close to 980 what is my percent error