Answer the following physics questions. Just the answer would be fine.

1. Calculate the value of the gravitational eld strength g. 250 km above the surface of Earth. {rE = 6.38 x 10% m, ME = 5.98 x 124 kg) 2. The lntemational Space Station is in orbit about 420 km above the surface of Earth. Calculate how many minutes it would take for the 188 to complete one orbit. {rE = 6.33 x 10\"6 m. ME = 5.98 x 10*24 kg) 3. How much work is done against gravity to move a 1'20 kg weather monitor 12!) km into the air? (rE = 6.33 x 10%? m, ME = 5.93 x 10"\"24 kg) 4. List TWO differences between charging an object by contact and charging an object by friction 5. Two equal charges of magnitude 1.1 x 1\"-?C experience an electrostatic force of 4.2 x 1U\"4N. How far apart are the centres of the two charges? 6. Calculate the electric eld 1.!) m from a small sphere with a positive charge of 3.2 x 1OABC. Describe the direction as outwards or inwards. i". A uniform electric eld has a strength of 120 MIC. An alpha particle with a charge +2e is pushed against the eld direction by an external force for a distance of 25 cm. How much electric potential energy does the alpha particle gain? 8. In a Millikan-type experiment. two horizontal parallel plates are 1.0 cm apart. A sphere of mass 2.2x1f-13 kg remains stationary when the potential difference between the plates is 350 V with the upper plate negative. a) Is the sphere positively or negatively charged