Classical Mechanics Answers

an accelerometer consists of a 50.0g object sliding on a frictionless horizontal surface. The object is attached to spring . When the object subjected to a steady acceleration of 0.80g. The object moves to x=5.0 cm away from its equilibrium position. Calculate the change in the elastic potential energy of the system.

If pulleys shown in the diagram are smooth and massless and A1 and A2 are acceleration of blocks of mass 4 kg and 8 kg respectively,then

A brick is resting on a rough wooden plank that is inclined at an angle theta relative to the horizontal. The friction force acting on the brick, along the incline, is
1 : zero.
2 : equal to the weight of the brick.
3 : greater than the weight of the brick.
4 : less than the weight of the brick.

A box of inertia m is pulled with a constant acceleration a along a horizontal frictionless floor by a wire that makes an angle of 15° above the horizontal. If T is the tension in this wire, then what is T compared to ma? Is T=ma? Is T<ma? Is T>ma?

A block with a mass of m crosses a rough horizontal surface at a constant speed of v. The coefficient of kinetic friction between the block and the surface is μ. How much power must be produced in order to overcome the friction force?

Compare the use of D’Alembert’s Principle and the Principle of Conservation of Energy to solve the following problem. Use diagrams to illustrate your answers.


A car with a mass of 1200kg accelerates up a road with a slope of 1 in 6, increasing its speed from 10kmh-1 to 60kmh-1, while travelling along the road a distance of 120m, against a frictional resistance of 800N. Calculate the tractive effort (force) required to propel the car up the hill.

A particle of mass m falls a given distance z0 in time t0=√2z0/g and the distance travelled in time t is given by z=at+bt^2 where constants a and b are such that the time t0 is always the same.show that integration 0 to t0 L dt is an extremum for real values of coefficient s only when a=0 and b= g/2.

A 2.0 kg mass is dropped from a height of 6m. Once it has fallen 6m it lands on a platform that is supported by a spring with a spring constant of 500 N/m.
Include a diagram

a) How fast is the mass going right before it makes contact with the platform? /5
b) How far will the spring compress? /5

A car is moving around a banked curve of radius 86 m at a constant speed. The road is banked at an angle of 11° and the car is moving at just the correct speed to ensure that there are no lateral frictional forces on the tyres - that is the only forces acting on the car are the force of gravity and the normal force from the road.

At what speed is the car moving? (in m s−1 to 2 s.f

A 5.0 kg drone is flying perfectly horizontally above the earth’s surface at a height of 40 m and a speed of 15 m/s. It then drops down to a height of 25 m (still horizontally) and reduces its speed to 6 m/s. What is the amount of work that is done on the drone to change its mechanical energy in this way?