Mechanics | Relativity Answers

A bullet of mass 0.05kg travelling horizontally at 30ms^-1 embeds itself in wooden block of mass 0.95kg.if the block is suspended by a light vertical string 1m long calculate the maximum inclination of the string at the horizontal

A lead bullet of mass 50g is fired with velocity 300ms^-1 into a lead block of mass 0.75kg, given that the lead block can move freely, calculate the combine speed of the bullet and the block after the impact

A motorbike goes uphill from point A to point B and down to point C takes 32.5(seconds). Know that during the movement of the car, the wind continuously creates a thrust of 1.4N. The coefficient of friction between the wheel and the road surface is constantly changing and decreasing as a function of μ=0.05e^(-0.05t), t in seconds. If the initial speed of the car at A is 2.5 times the speed of the car at B and 1.5 times the speed at C and the distance AC=158m, the angle of inclination between AB and the road surface at C is 30°, then the distance AB must be long. How many meters at least?

A frog has fallen into a pit that is 30m deep.Each day the frog climbs 3m, but falls back 2m at night.How many days does it take for him to escape?

A 120N force applied horizontally drags a 4kg load along a horizontal table at a uniform velocity of 3m/s (a) what is the coefficient of kinetic friction between the load and the table (b) if the applied force is suddenly removed,how much further does the load slide before coming to a stop

The cliff is 22 meters high.You fell in the water 5 meters away from the hill.what is your initial velocity?

Three children are trying to balance on a seesaw, which consists of a fulcrum rock,

acting as a pivot at the center, and a very light board of 3.6 m long. Two playmates

are already on either end. Boy A has a mass of 50 kg and Girl B and Girl C have

masses of 35 kg and 25 kg respectively.

(a) The Girl C is now sits at a distance x from the fulcrum to balance the seesaw.

Calculate x.

(b) If the weight of the board is to be considered, would distance x increased,

decreased or remain the same as in part (a)?

A block is pulled across a rough, horizontal surface from point A to point B by a

force, P as shown in the figure. The magnitude of the force of friction acting on

the block between A and B is 1.2 N, and points A and B are 0.50 m apart. If the

kinetic energies of the block at A and B are 4.2 J and 5.8 J, respectively, how

much work is done on the block by the force P between A and B?

2. A 12.6 kg block is connected to a 28.0 kg of bucket full of steel ball by a

string through a frictionless pulley as in the figure below. When the block is in

motion, the kinetic friction force on the surface of the table is 8.96 N.

a. Draw a free-body diagram for both block and bucket.

b. Calculate the acceleration of both block and bucket. Give your

answer in two decimal places.

1. A loaded sled weighing 85 N rests on an inclined plane at an angle of 15 o to

the horizontal as in the figure below. The coefficient of static friction between

the sled and the inclined plane is 0.25. Calculate the minimum force, F

parallel to the inclined plane, that will prevent the sled from slipping down.