Theresa is swinging a 4. 0 kg ball on a 1. 2 m long rope with a tangential speed of 1. 8 m/s. What is the centripetal force exerted on the rope? Round to the tenths place. N.

Aplanet of mass m 6.75 x 1024 kg is orbiting in a circular path a star of mass m 2.75 x 1029 kg. the radius of the orbit is r 8.05 x107 km. what is the orbital period (in earth days) of the planet tplanet?

How many seconds does it take a pebble released from rest off a bridge to fall 29.4 m ? what is the pebble's speed when it has fallen 29.4 m ?

Explain to someone who knows nothing about fossils the study of invertebrate paleontology and how it scientists understand the history of the earth. be sure your explanation contains a minimum of two complete sentences.