Mechanics | Relativity Answers

a stunt car traveling toward the edhe of a cliff at 25 meters per second lands 50 meters measured horizontally from the edge of the cliff.

a.)how much time does it take the car to reavh the ground

b.)determine the height of the cliff.

An object is in simple harmonic motion with the equation of motion as x=Acos(ωt+φ),when t=T/2,the velocity of the object is......?

If you use a marble of radius 13 mm for mercury, how far from the sun must you place your outpost planet?

• A monochromatic light of wavelength λ=600nm illuminates a grating with normal incidence. The diffraction angle corresponding to the second order principle maximum is 30°and the third order is missing. (1) What is the grating spacing (a+b)? (2) what is the possible least width of a ruling a? (3) If the spacing and the ruling are given as above, find all the possible orders of principle maximum in the range of -π/2<θ<π/2 ?

• In Young's double - slit experiment, a monochromatic parallel light of wavelength, λ=550 nm illuminates the double slits with separation of a=2×10⁻⁴m. The distance between the viewing screen and the barrier containing the double slits is D=2m. Find : (1) The distance between the pair of the tenth order bright fringes that are on both sides of the central maximum? (2) If one slit is covered by a glass sheet of thickness =6.6×10⁻⁵ m and index of refraction n=1.58, the zeroth maximum will move to a new position which corresponds to the original Kth order bright fringe. What is the value of K?

• A sinsoidal wave with amplitude A= 0.1m, period T=1/2 s, and wave length λ=10m. When t=0, the element at the wave source happened to be at the positive maximum displacement position. If the wave source is the origin point of the x axis and the wave is travelling along the positive OX axis, find: (1) The wave function of this wave? (2) The displacement of the element at x₁=λ/4 when T₁=T/4? (3) The velocity of the element at x₁=λ/4 when T₂=T/2?

• Two equations of simple harmonic motion are given as follows : x₁= 4×10⁻² cos2π(t+1/8); x₂=3×10⁻² cos2π(t+1/4) . Find the equation of the resultant oscillation?

An advertisement claims that a centrifuge takes up only 0.127 m of bench space but can 

produce a radial acceleration of 3000g (it is simply 3000 times the value of 𝑔 = 9.8𝑚/𝑠

ଶ

) at 

5000 rev/min. Calculate the required radius of the centrifuge. Is the claim realistic?

Given that R = 25 cm, r = 10 cm and that the machine requires an effort of 500 N to lift a 100 kg mass, determine the:

i. velocity ratio

ii. weight of the 100 kg mass

iii. mechanical advantage

iv. efficiency

v. useful work done in lifting the mass through a height of 65 cm.

vi. law of the machine

A substance of mass m1 at a temperature of 300 K is supplied with 1000 J of energy such that its temperature increases to 350 K. When the same substance of mass m2 is supplied with 800J of energy, its temperature changes from 275 K to 305 K.

Determine the ratio of m1 to m₂