. 22. An electric kettle is required to heat 0.6 litre of water
from 10°C to boiling point in 5 min, the supply
voltage being 240 V. The efficiency of the kettle is 78
per cent. Calculate: (a) the resistance of the heating
element; (b) the cost of the energy consumed at
8.0p/kWh. Assume the specific heat capacity of water​

Ahot-air balloonist, rising vertically with a constant speed of 5.00 m/s releases a sandbag at the instant the balloon is 40.0 m above the ground. after it is released, the sandbag encounters no appreciable air drag. compute the velocity of the sandbag at 0.250 s after its release.

Compare the horizontal displacement of the two balls as they travel to the ground. what do you observe?

In a game of pool, ball a is moving with a velocity v0 of magnitude v0 = 15 ft/s when it strikes balls b and c, which are at rest and aligned as shown. knowing that after the collision the three balls move in the directions indicated and assuming frictionless surfaces and perfectly elastic impact (that is, conservation of energy), determine the magnitudes of the velocities va, vb, and vc.