Mechanics | Relativity Answers

A car of mass 1000 kg is cruising at 120 km/hr. At this velocity the drag and friction forces that the engine needs to work against is equivalent to 450 N.


Calculate the propulsive power delivered at the wheels when the car is cruising at 120 km/hr.
Give your answer in Watts

A car of mass 1000 kg is cruising at 120 km/hr. At this velocity the drag and friction forces that the engine needs to work against is equivalent to 450 N.


Q: Calculate the kinetic energy of the car when cruising at 120 km/hr.
Give your answer in Joules

A spring extends by a distance of 5 cm when subjected to a 10 N force.


Q: What is the amount of elastic potential energy contained in this spring when extended by 10 cm?
Give your answer in Joules and as a positive value.

A spring is subjected to a force of 40 Newtons at a rest position. When an additional load of 3 N is exerted the spring has moved by 20 cm. Calculate the spring constant k of this spring.

The 20 kg suitcase A is released from rest at point C of height 3 m from floor ED. The suitcase slides down a friction-less ramp between C and E and continues sliding on the floor until stopping at a certain distance from E.
The coefficient of friction between the floor ED and suitcase A is µ(ED) = 0.4.
Consider g = 9.8 m/s2
Calculate the distance in m from point E reached by suitcase A as it stops

The 20 kg suitcase A is released from rest at point C of height 3 m from floor ED. The suitcase slides down a friction-less ramp between C and E and continues sliding on the floor until stopping at a certain distance from E.
The coefficient of friction between the floor ED and suitcase A is µ(ED) = 0.4.
Consider g = 9.8 m/s2
Calculate the velocity reached in m/s at point E of suitcase A

A pressure gauge is connected to the working chamber of Cylinder 1 and measures its pressure P1.
A force F1 is acting on the piston push rod in the direction shown in the figure, with a magnitude of 100 Newtons.
The diameter of Cylinder 1 is given as 45mm.
Q: Calculate the magnitude of pressure P1 resulting from the force on the piston F1.
Give your answer in Pa.

One of the world's largest Ferris wheels, the Cosmo Clock 21 with a radius of 50.0 m is located in Yokohama City, Japan.
Each of the sixty gondolas on the wheel takes 1.00 minute to complete one revolution when it is running at full speed.
Note: Ignore gravitational effects.

What is the centripetal acceleration of the gondola when the Ferris wheel is running at full speed?

A car travels at a constant speed around a circular track whose radius is 3.90 km. The car goes once around the track in 292 s. What is the magnitude of the centripetal acceleration of the car?

A 14 g block of metal (Cs = 126) heated to 78 is plunged into 405 g of water at 24 degree C. What is the equilibrium temperature? Cs of water is 4190 Jkg-1K-1. Give your answer to 1 decimal place