The radius of the wheel is 40cm and the radius of the axle is 0.1 metre in a wheel and

axle. If a load of 1200N is overcome up to 4m by applying

an effort of 400N, calculate:

i. mechanical advantage ii. velocity ratio iii. efficiency

iv. output work v. input work ​

If a substance is in the gas phase, which of qualities of the gas will stay constant? a: volume b: mass c: shape d: position of particles

The ultracentrifuge is an important tool for separating and analyzing proteins. because of the enormous centripetal accelerations, the centrifuge must be carefully balanced, with each sample matched by a sample of identical mass on the opposite side. any difference in the masses of opposing samples creates a net force on the shaft of the rotor, potentially leading to a catastrophic failure of the apparatus. suppose a scientist makes a slight error in sample preparation and one sample has a mass 10 mg larger than the opposing sample. if the samples are 12 cm from the axis of the rotor and the ultracentrifuge spins at 70,000 rpm, what is the magnitude of the net force on the rotor due to the unbalanced samples? ( be thorough on your answer)

What is friction? how does it affect the motion of an object?