Mechanics | Relativity Answers

A block weighing 7 N requires a force of 2.7 N to push it along at constant velocity.
What is the coefficient of friction for the surface?

Why wavelength is short initially in black body when it emits radiation?

The block of material shown below has a shear modulus of 65 GPa. Determine the shear stress and the shear strain induced by the 6 kN shearing force

A motor boat on the river to move from point A from a float on the water outpaces supplies.After 60 minutes the boat changes direction and then again to the board at a distance of 6 km from point A appears.If boats can be assumed to be constant, to find water flow rate

A 10 kilogram shell is fired from a 500 kilogram gun with a velocity of 1000 m/sec. What is the recoil velocity of the gun?

A racing car, moving with constant acceleration along a straight stretch of track, passes a fixed marker A with speed of 72 km/h. Two seconds later it passes a second fixed marker B. Given that the distance AB is 45 meters, find the acceleration of the car.


A third marker C is situated near the end of this section of track. Given that the speed of the car as it passes C is 216 km/h, find the time taken by the car to travel from A to C.

hi dear friend i have question about that if work is scalar quantity so if we add angle with work formula what is the ans scalar or vector

Example:

W= F.d.cosθ=vector or scalar

Thanks Hanifullah Hemat ,Afghanistan

A regular pentagon ABCDE is jointed at the angles and stiffened by two jointed bars AC and AD. Two opposite forces P, each 3 Newton are applied at B(direction:<---)and E (direction:--->). Find the force in each bar of the framework, stating whether it is tensile or compressive.

1. Show that the basis of dimensional analysis that the following relations are correct.
a). v2-u2 = 2aS, Where (u) is the initial velocity, (v) is final velocity, (a) is acceleration of the body and (S) is the distance moved.
b). p = 3g/4rG, where (p) is the density of earth, (G) is the gravitational constant, (r) is the radius of the earth and (g) is acceleration due to gravity.

I used a 7.5 kg wheelbarrow to carry a 35 kg rock. If the rock is placed with its centre of gravity 0.2 m in front of the wheel and the centre of gravity of the wheelbarrow is 0.1 m in front of the wheel what force must be applied to the handle 0.6m from the wheel to keep the wheelbarrow horizontal?