Mechanics | Relativity Answers

A rifle is found to give the bullet a muzzle velocity of 485 m/s the barrel is 80cm long
a) how much time is the bullet moving in the barrel?
b) what is the average acceleration of the bullet?

If both animals are running at full speed,
with the gazelle 55.1 m ahead, how long before
the cheetah catches its prey?
Answer in units of s.

An 1850 kg car is moving to the right at a constant speed of 1.44 m/s . What is the net force on the car ?

Prove that VcA = vccb +VBA when a,b,c don't pass through same event

A 5kg box rest on an inclined plane with angle of inclination 30degree. calculate the force required to keep, if there is no sliding down the plane given that the coefficient of friction is 0.30

proove that vector A=3i+j-2k B=-i+3j+4k C=4i-2j-6k can form the sides of a triangle and find the length of the median of the triangle.

In which of the following situations would it be harder to drive around a bend without skidding?
1)Slow speed in a sharp (tight) bend
2)Slow speed in a gentle bend
3)High speed in a sharp (tight) bend
4)High speed in a gentle bend

Fc=mv2/r
Fc is centripetal force, m is mass, v is speed and r is radius


6. What will happen to the size of the centripetal force if the mass (m) is doubled?


1)No change
2)The centripetal force doubles
3)The centripetal force increases by a factor of 4
4)The centripetal force is halved

A body at rest is at initial acceleration for 30s. After 30s which acceleration is reduced to 5m/s^2 for the bext 20s. The body then maintains the speed attained for 60s after which brought to rest in 20s. Draw the velocity time graph of the motion using the information given above to calculate,(a)maximum speed (b)average as the body is been brought to test (c) total distance travelled during the same 50s (d) average speed during the same interval

A body at rest is at initial acceleration for 30s. After 30s which acceleration is reduced to 5m/s^2 for the bext 20s. The body then maintains the speed attained for 60s after which brought to rest in 20s. Draw the velocity time graph of the motion using the information given above to calculate,(a)maximum speed (b)average as the body is been brought to test (c) total distance travelled during the same 50s (d) average speed during the same interval