Mechanics | Relativity Answers

A concrete sphere of radius R , has a cavity of radius of r which is packed of saw dust. the specific gravity of concrete and saw dust are 2.4 and 0.3 . the sphere floats with its entire volume submerged under water calculate the ratio mass of concrete and saw dust?

can we design aeroplane which light but sufficiently strong?how?

a child is sitting on a swing .its minimum and maximum heights from the ground are 0.75m and 2m resp. its maximum speed will be

Sally drives 29.0 min at 59.0 km/h, 35.0 min at 45.0 km/h and 45.0 min at 69.0 and she spends 6.0 min eating lunch and buying gas, determine the average speed

a ceiling fan rotating at its full speed of 1200rpm is swithched off at t =0 .it cums at rest at t=5 s assuming uniform motion ,the no. of revolution made by it b4 cuming to rest ??

a particle of mass 2kg with velo. 10 m /s moving along a line x+y=2 its angular momentum abt pt. (2,0) will b??

A 400 gram bead slides on a curved wire, starting from rest at point A in the figure below. If the wire is frictionless, find the speed of the bead (a) at B and (b) at C.

starting at rest t=0,a wheel undergoes a constant angular acceleration .when t=2.33sec, the angular velocity of a wheel is 4.96rad/s.the acceleration continues until t=23.0s,when it abruptly ceases. through what angle does the wheel rotate in the interval t=0 to t=46.0s?

An object initially at rest breaks into two pieces as the result of an explosion. One piece has twice the kinetic energy of the other piece. What is the ratio of the masses of the two pieces? Which piece has the larger mass?

a good baseball pitcher can throw a baseball towards home plate at 85mi/h with a spin of ball1800rev/min. how revolution does the baseball make on its way to home plate?for simplicity , assume that the60 ft trajectory is a straight line.