Mechanics | Relativity Answers

An object initially at rest accelerates uniformly at 5 m/sec west decelerates uniformly at 4.0 m/sec^2 for 2.0 sec. What is the displacement of this object?

An object is allowed to fall freely near the surface of a planet. The object falls 45 m in the first 3.0 sec. The acceleration due to gravity o this planet is...?

A rock is dropped from a cliff. Approximately how long does it take to fall 45m if the acceleration due to gravity is 9.8 m/sec^2?

Which of the following is a vector quantity?
distance, displacement, time or
mass?

Iron ball and aluminium cube are completely of the same volume submerged to the water. Compare the Archimedes forces acting on them.

What is the distance?

You are told that an object has zero acceleration. Two forces acting on the object ar f1=3.6N at 74 degress below the +x axis and f2=3.6N above the -x axis. What is the 3rd force on the object?

Two blocks connected by a string are pulled
across a rough horizontal surface by a force
applied to one of the blocks, as shown.
The acceleration of gravity is 9.8 m/s2
If each block has an acceleration of 2.5 m/s2
to the right, what is the magnitude of the
applied force?
Answer in units of N.

A ball is thrown at the edge of a cliff 90.0m high at 42m/s. Calculate A.) the time required to hit the ground below. B.) the velocity. C.) the velocity when the ball is 60.0m above the ground

Here is the questions I need help with.
The barrels of the 16 inche gun and 15 m long. The shells each had a mass of 1300kg ans were fired with sufficient explosive force to provide them with a muzzle velocity of 760 m/s . Use the work energy principle to determine the explosive force that was applied to the shell within the barrel of the gun. Express you answer in newtons and pounds.