Problems on speed and Velocity

Topic:Acceleration

Acceleration is the change in velocity ,which refers to "the rate at which an object changes its position" over time.

Here is a some simple problems on acceleration,which helps you to find speed of a moving object.

1. A bicyclist starts down a ramp, traveling at a speed of 2.8m/s, and then accelerates at 0.25m/s^2 for 18s. What is his speed at the bottom of the ramp

ANSWER: 7.3m/sec

V initial=2.8m/s

Acceleration=0.25m/s^2

Time=18s.

V final=?

V final= V initial+ Acceleration* Time =2.8+ (0.25*18) = 7.3m/sec

2.A race car traveling at 55m/s, slows down to 9m/s with an acceleration of-9.2m/s^2 to take a corner. How long does it take the race car to slow down?

ANSWER: 5 seconds

V initial=55m/s

V final=9m/s

Acceleration=-9.2m/s^2

Acceleration= V final- V initial/ Time

Time=9m/s-55m/s/9.2m/s^2=5 seconds

I hope it helped you ,for more physics help reply me