A spherical balloon of volume 4.00 x 10 -3 m contains helium at a pressure
of 1.20 x105 Pa. How many moles of helium are in the balloon if the average
kinetic energy of the helium atoms is 3.60 x 10-22 J?

The seven sisters, seven stars located more than 400 light-years away in the taurus constellation can be seen here with venus and another constellation, orion. the seven stars stay grouped together but seem to move, like the planet venus. why do stars seem to move like planets in the night sky?

Astone weighing 1.5 kilograms is resting on a rock at a height of 20 meters above the ground. the stone rolls down 10 meters and comes to rest on a patch of moss. the gravitational potential energy of the stone on the moss is joules.

You've already seen the value of 9.8 in this lesson. what's this value called? what quantity does it represent?