Mechanics | Relativity Answers

At what point will the speed of a projectile be maximum? calculate the range of projectile.

An Fm radio station broadcasts electromagnetic radiation at a frequency of 101.2MHz. The wavelength of this radiation is __________m.

If an oscillatory motion must be simple harmonic, the restoring force F must obey ------------------ law for small displacements from equilibrium position

Blocks A (mass 3.00 kg ) and B (mass 14.00 kg , to the right of A) move on a frictionless, horizontal surface. Initially, block B is moving to the left at 0.500 m/s and block A is moving to the right at 2.00 m/s. The blocks are equipped with ideal spring bumpers. The collision is headon, so all motion before and after it is along a straight line. Let +x be the direction of the initial motion of A. The questions Part A Find the maximum energy stored in the spring bumpers. Uspringmax = Part B Find the velocity of block A when the energy stored in the spring bumpers is maximum. . vA = Part C Find the velocity of block B when the energy stored in the spring bumpers is maximum. vB = Part D Find the velocity of block A after the blocks have moved apart. vA = Part E Find the velocity of block B after the blocks have moved apart. . vB = need units

Nancy is playing on a ladder and slide. The entry point of the slide is 3.0 meters above the ground and the slide is inclined at an angle of 30.0° with the horizontal. What is Nancy’s displacement each time she slides down from the top?

Which of these is not a statement of newton's law of universal gravitation?

a) gravitational force between two particles is attractive as well as repulsive

b) gravitational force acts along the line joining the two particle

c) gravitational force is directly proportional to the product of the masses of particle

d)gravitational force is inversely proportional to the square of the distance of the particle a part

How large an average force is required to stop a 1400-kg car in 5.0 s if the car's initial speed is 25 m/s?

a)2000 N

b)3500 N

c)9000 N

d)7000 N

Sand drops at the rate of 2000 kg/min. from the bottom of a hopper onto a belt coveyor moving horizontally at 250 m/min. determine the force needed to drive the conveyor, neglecting friction?

a)500 N

b)800 N

c)139 N

d)152 N

The exhaust gas of a rocket is expelled at the rate of 1300 kg/s, at the velocity of 50 000 m/s.find the thrust on the rocket in newtons?

A uniform plank AB 30 m long, weighing 100 N is pivoted at point P,Q which are 5 m from the ends A and B respectively.A boy of weight 250 N stand at apoint D on the plank,1 m away from Q and the arrangement is in equilibrium.Determine the reaction R1 and R2 at the supports ?

a)77.5 N, 245.5 N

b)105.5 N 33.5 N

c)37.5 N, 312.5 N

d)27.5 N, 232.5 N