Answer:
Static, sliding, and rolling friction occur between solid surfaces. Static friction is strongest, followed by sliding friction, and then rolling friction, which is weakest. Fluid friction occurs in fluids, which are liquids or gases.
Explanation:
(186,000 mi/sec) x (3,600 sec/hr) x (24 hr/da) x (365 da/yr)
= (186,000 x 3,600 x 24 x 365) mi/yr
= 5,865,696,000,000 miles per year (rounded to the nearest million miles)
Work done = 0.5*m*[(v2)^2 - (v1)^2]
where m is mass,
v2 and v1 are the velocities.
Given that m = 1.50 x 10^3 kg, v2 = -15 m/s (decelerates), v1 = 25 kg,
Work done = 0.5 * 1.50 x 10^3 * ((-15)^2 - 25^2) = 3 x 10^5 joules
Just ignore the negative value for the final result because work is a scalar quantity.
