Mechanics | Relativity Answers

An insect of mass 20 g crawls from the centre to the outside edge of a rotating disc of
mass 200g and radius 20 cm. The disk was initially rotating at 22.0 rads−1
. What will be
its final angular velocity? What is the change in the kinetic energy of the system?

A truck of mass 2000 kg moving on a highway experiences an average frictional force of 800 N. If its speed increases from 25 ms-1 to 35 ms-1 over a distance of 500 m, what is the force generated by the truck.?

A box of mass 50 kg is placed on an inclined plane. When the angle of the plane is increased to 30º, the box begins to slide downwards. Calculate the coefficient of static friction between the plane and the box. Draw the free body diagram.

A car accelerates from rest at 3m/s2 along a straight road. How far has the car travelled after 4s?

Messy with a mass of 440 lbs walks up a flight of stairs 120 centimeters high in 30 seconds. What power has she used? Express your answer in horse power.

A box of mass 50 kg is placed on an inclined plane. When the angle of the plane is
increased to 30º, the box begins to slide downwards. Calculate the coefficient of static
friction between the plane and the box. Draw the free body diagram.

stretching of rubberband result in what

Two collinear harmonic oscillations x1 = 8 sin (100 πt) and x2 = 12 sin (96 πt) are superposed. Calculate the values of time when the amplitude of the resultant oscillation will be (i) maximum and (ii) minimum.

A spring-loaded toy gun projects a 4.5-g nerf pellet horizontally. The spring constant is 8.5 N/m, the barrel of the gun is 15 cm long, and a constant frictional force of 0.026 N exists between the barrel and the nerf pellet. If the spring is compressed 7.0 cm for this launch, determine the speed of the pellet as it leaves the barrel. (Assume the pellet is in contact with the barrel for the full length of the barrel.)

A 73-kg boy is surfing and catches a wave which gives him an initial speed of 1.6 m/s. He then drops through a height of 1.55 m, and ends with a speed of 8.5 m/s. How much nonconservative work was done on the boy?