Mechanics | Relativity Answers

by what factor does the density of an object change when it's move with speed v?
1)(1-v²/c²)

2)1/(1-v²/c²)

3)1/√(1-v²/c²)

In the distance future, Ben is in a rocket ship. He passes Jerry. Jerry measures the time it takes Ben's ship to pass him and finds that t=4.03μs. Ben measures the length of the ship to be l=203 m.
a) According to Jerry, what speed is the rocket travelling at?
b) According to Jerry what is the length of the ship?
c) Ben measures the time for the ship to pass Jerry. He turns on his clock when the front of the ship passes Jerry and turns it off when the back of the ship passes Jerry. What time does Ben measure?

A 4 kg ball is propelled off a track with a force 200 N. The force of gravity on the ball is
40 N. Determine the resultant force on the ball

A spelunker os surveying a cave.she follows a passage 180m straight west then 210m in a direction 45 degrees east of south,and then 280m at 30 degrees east of north after a fourth unmeasured displacement,she finds her self back where she started.use a scale drawing to determine the magnitude and direction of the fourth displacement.

in using a vernier scale reading to measure an object, the main scale reading was read to be 0.7cm and vernier scale reading to be 3cm. find the actual measurement of the object

The force of resistance on an object moving through a fluid is proportional to the square of its velocity. The initial velocity of an object of mass 1 kg moving through the fluid is 40 ms^−1. After 5 s the velocity reduces to 20 ms^−1. Calculate its velocity after
10 s.

The radius of the moon is one-fourth, and its mass is one eighty-first that of the earth. If the
acceleration due to gravity on the surface of the earth is 9.8 m/s2, what is its value on the
moon’s surface.

Mary's friend observes the investigation and claims that block B has more mass. If there were no errors in the investigation, which of the following must be TRUE for this claim to be correct?
A.
Block B must have greater density than block A.
B.
Block B must be larger than block A.
C.
Block B must be longer than block A.
D.
Block B must have more volume than block A.

In a horizontal uniform electric field, a small charged disk is gently released on the top of a fixed spherical dome. The disk slides down the dome without friction and breaks away from the surface of the dome at angular position ? = sin–1 (3/5) from the vertical. Determine the ratio of the force of gravity acting on the disk to the force of its interaction with the field.

Artificial satellite revolves around the earth in 2.5 hours in a circular orbit . Find the height of satellite above the earth assuming earth as a sphere of radius 6370 kilometre.