Mechanics | Relativity Answers

At a point along the line joining the centres of the earth and moon, the gravitational forces they exert on a third body are equal in magnitude but in opposite directions. Determine the distance of this point from the centre of the moon, in terms of 'x', You may take the mass of the earth to be 81 times the mass of the moon, and the distance between the centres of the earth and moon to be 'x'.

an oil tankers engine have broken down, and the wind has accelerated the tanker to a speed of 1.5 m/s straight towards a reef. when the tanker is 500m from the reef the wind dies slowly as the engineers gets the engine running. the rudder is stuck, so the only choice is to try to accelerate straight backward away from the reef. the mass of the tnker and cargo is 36000000kg, and the engines produce a net horizontal force of 80000N on the tanker. will the ship hit the reef? provide full justification for your answer

A 2400 W engine pulls a 200 kg block at constant speed up a 12.0 m long, 25.0° incline. Determine how long does it take to cover this distance.

a) The speed of an aeroplane is .ms12001− The engines take in 80 kg of air per second and mix it with 40 kg of fuel. This mixture is expelled after it ignites and it moves at a velocity of 1ms3000−relative to the aeroplane. Calculate the thrust of the engine

a child pushes his friend in a wagon along a horizontal road and then lets go The wagon rolls for 10.0 second before stopping. It travel a distance of 20 cm during the last 1.00 s of its motion. Assuming uniform acceleration. A) how fast was the wagon travelling at the instant the child released it ? B) HOW FAST WAS THE WAGON TRAVELLING WHEN IT HAD COVERED HALF OF THE TOTAL DISTANCE

A foot ball punter wants to kick the ball so that it hits the ground 50 m from where it is kicked and so that the ball is in the air 4 seconds. at what angle and with what initial speed should the ball be kicked? assume that the ball leaves the kicker's foot from an elevation of 1 meter

a circular disc rotates on a thin air film with a period of 0.3second. its moment of inertia about its axis of rotation is 0.06kg/m*2.a small mass is dropped onto the disc and rotates with it. the moment of inertia of the mass about axis of rotation is 0.04kg/m*2.determine final period of rotating disc and mass?

can we move a merry go round by applying a force along the radial direction? explain in detail

suppose you are designing a cart for carrying goods downhill. to maximize cart speed should you design wheels so that their moment of inertia about their rotation axes are large or small or it does not matter?explain in detail assuming that mechanical energy is conserved.

Obtain an expression for the time period of a satelite orbiting the earth. A space shuttle is in a circular orbit at a height of 250km from the earth's surface, where the acceleration due to earth's gravity is 0.93g. calculate the period of its orbit. Take g=9.8m/s-2 and the radius of the earth R=6370000m.