Mechanics | Relativity Answers

A cardboard box is sliding across the floor after some initial push gets it moving. The box is not being pushed anymore, just sliding across the floor. The floor is exerting friction on the box. What will happen to the box and why?

You are operating a remote - controlled model car on a vacant tennis court . Your position is the origin of coordinates , and the surface of the court lies in the -plane . The car, which we represent as a point , has x- and y- coordinates that vary with time according to x = 2.0m - (0.25 m/s ^ 2) * t ^ 2; y = (1, 0 m/s) * t + (0.025 m/s ^ 2) * t ^ 2 a ) Find the car's coordinates and its distance from you at time t=2.0 s. b ) Find the car's displacement and average velocity vectors during the interval from Ostot t=2.0 s. c ) Find the components of the average acceleration in the interval from t = 0.5to; t=2.0 s. 

A body falls freely from the rest, Find:

A. Distance it falls in 5 sec.

B. Velocity after falling 5 km.

C. Time required to attain a velocity of 50 m/s.

D. Time in which it falls 200 m.

A hovercraft passes point A moving West with a speed of 15 m s−1.

The hovercraft immediately begins to accelerate at a steady rate of 0.13 m s−2 North.

What is the magnitude of the velocity of the hovercraft 200 s after it passes point A? (in m s−1)

Give your answer to 2 s.f.

(note: a hovercraft rides on a cushion of air and so does not contact the ground and experiences no frictional forces)

A hollow cylinder and a solid cylinder have the same mass and the same diameter. They are released at the same time from rest from the top of an incline. Which will reach the bottom first?

projectile is fired with an initial velocity of 193.2 feet per second upward at angle of 300to the horizontal from point 257.6 feet above a level plain. What horizontal distance will it cover before it strikes the level plain? A dart is thrown horizontally with an initial speed of 10 m/s toward point P, the bull's-eye on a dart board. It hits at point Q on the rim, vertically below P, 0.2 s later. What is the distance PQ? How far away from the dart board is the dart released? 3 Find the angle of elevation of a gun which fires a shell with muzzle velocity 366 m/s at a target on the same level but 4,575 m distant.

Calculate the average acceleration needed by a train travelling initially at 12m/s[E] to stop in 120s.

A tie member of length 3.0 m between the intersection carries ultimate axial tension of 325 kN. The end connection is to be made using M20 bolts of product Grade C and property class 4.6. The grade of steel is E250. Design a pair of equal angle section placed on each side of gusset plate. Draw schematic diagram showing Plan and Section

A pilot is required to fly directly from London, UK, to Rome, Italy.In order toarrive in Rome on time, the velocity of the plane relative to the ground must be 400 km/h [S43°E].If a wind is blowing with a velocity of 75 km/h [S], determine what the velocity of the plane relative to the air must be in order for the pilot to arrive in Rome on time.

An aircraft traveling with a velocity relative to the air of 320 km/h [S62°W] passes over Winnipeg.The wind velocity is 72 km/h [S].Determine the velocity of the plane relative to the ground.