Physics Answers

A 1205 kg car is running a speed of 35 m/s along a level road. How large a constant retarding force is required to stop it in 15 s? 

A man runs around a circular track of 800 meters radius for 30 seconds, starting at a point directly to the right of the center and goes in a counterclockwise manner. He goes 5 meters per second for the first 15 seconds, runs 90 meters for the next 6 seconds and then 180 meters for the rest of the course. What was his average speed?

An equipotential surface that surrounds a + 5.0 μC point charge has a radius of 5.0 cm. What is the potential of this surface? *

A particle of mass 10kg is placed on a rough plane inclined at angle of 30degree to the horizontal. What horizontal force is required to move up the plane

A car is being driven along a road at 25 m s-1 when the driver suddenly notices that there is a fallen tree blocking the road 65 m ahead. The driver immediately applies the brakes giving the car a constant acceleration of -5 m s-2.  How far in front of the tree does the car come to rest?

In travelling the 70 cm along a rifle barrel, a bullet uniformly accelerates from rest to a velocity of 210 m s-1. Find the acceleration involved and the time taken for which the bullet is in the barrel.

A car is being driven along a road at 25 m s-1 when the driver suddenly notices that there is a fallen tree blocking the road 65 m ahead. The driver immediately applies the brakes giving the car a constant acceleration of -5 m s-2.  How far in front of the tree does the car come to rest? Ans: 2.5 m before.

A cyclist accelerates from 0 m/s to 8 m/s in 3 seconds.What is his acceleration?Is this acceleration higher than that of a car which accelerates from 0 to 30 m/s in 8 seconds ?

A person has a reasonable chance of surviving an automobile crash if the deceleration is no more than 30 g's.

a. Calculate the force on a 68-kg person accelerating at this rate.

b. What distance is traveled in meters if brought to rest at this rate from 95 km/h?