Mechanics | Relativity Answers

A turn of radius 20 m is banked for the vehicles going
at a speed of 36 km/h. If the coefficient of static friction
between the road and the tyre is 0.4, what are the
possible speeds of a vehicle so that it neither slips down
nor skids up ?

1. A solid cube with mass 80 kg Is put in an elevator. The length of each side is 40 cm. The elevator is moved up and down repeatedly. When It moves upward, it able to reach speed 5 m/s in 4 seconds, while when It moves downward It able to reach speed 8 m/s in 2 seconds. Find the pressure experiences by the elevator caused by the solid cube, when:
a. it moves downward
b. it moves upward
c. It moves with constant speed 1 m/s
d. What you can conclude based on the result on a, b, and c?

A hollow cylinder is made of gold. The mass of the object is 702,24 kg and the volume enclosed by the outside surface of the cylinder is 49,28 x 10-3 m3. What Is the radius of the cylindrical cavity if the height is 20 cm? gold = 19000 kg/m3

Suppose you walk 12.5m in a direction exactly 23 degrees south of west then you walk 21m in a direction exactly 44 degrees west of north
for part A (I got) was The resultant, 28.03 meters
Now part b says:

What is the angle of the compass direction of a line connecting your starting point to your final position measured North of West in degress?

A player hits a football which is initially at rest and moves 22 m/s.
Find the:

a. momentum of the football if it has a mass of 0.48 kg
b. force exerted on it when the time of contact is 0.03s
c. impulse in the football

Vector
a⃗
a→
of length 8 m lies at an angle of
60o
60o
above the x-axis in the first quadrant. Vector
b⃗
b→
of length 5 m lies
53o
53o
below the x-axis in the fourth quadrant. Determine the magnitude of
a⃗ −b⃗

At a bullet fired with a initial velocity of 900 ms at a target located 150 ft from rifle. How much time is required for the bullet to reach the target?

A bicycle racer sprints at the end of a race to clinch a victory. The racer has an initial velocity of 11.5 m/s and accelerates at the rate of 0.650 m/s2 for 7.00 s.What is his final velocity? The racer continues at this velocity to the finish line. If he was 300 m from the finish line when he started to accelerate, how much time did he save? One other racer was 5.00 m ahead when the winner started to accelerate, but he was unable to accelerate and traveled at 11.7 m/s until the finish line. How far ahead of him (in meters and in seconds) did the winner finish?

A cricket ball of mass 150 grams is delivered from a hand of a fast bowler at a speed of 90000 m/s. The batsman strikes the ball with a bat of mass 900 grams causing the ball to go straight down the ground with a momentum of 162 kgm/s. What is the velocity of the bat before collision, given that the bat comes to rest after striking the ball.

Show, using a mathematical calculation, why a stationary object has no momentum