18. a. Derive an expression for time period of a simple pendulum using dimensional analysis. b. A calorie is a unit of heat or energy and it equals about 4.2 J where 1 J = 1 kg m2 s-2. Suppose we

employ a system of units in which the unit of mass equals α kg, the unit of length equals β m, the unit of time

is γ s. Show that a calorie has a magnitude of 4.2 α-1 β-2 γ2 in terms of the new units

(pls answer fast I need this answer urgently )​

A30 kg weight lies on top of a massless piston of area a = 0.01 m2 the exterior air is at a (constant) p =1 atm and t = 27 c. the interior gas is 0.4 moles of (ideal) n2 and it has initial temperature 27.00 degrees c. 1. what is the initial pressure in the interior? a. 29.4 kpa b. 130.7 kpa c. 101.3 kpa the next three questions concern what happens when an amount of heat q is slowly added to the interior, raising the piston by 1 mm and raising the interior temperature to 27.40 c

What kind of simple machine is a catapult?

If there's a small amount of friction between two surfaces, the result could be select all that applya. no movement b. heatc. a little bit of movementd. sliding around