two point charges each experience a 1-n electrostatic force when they are 2 cm apart. if they are moved to a new separation of 8 cm, what is the magnitude of the electric force on each of them?
2 n
1/8 n
1/16 n
1/4 n
1/2 n

Asmall metal bar, whose initial temperature was 10° c, is dropped into a large container of boiling water. how long will it take the bar to reach 70° c if it is known that its temperature increases 2° during the first second? (the boiling temperature for water is 100° c. round your answer to one decimal place.) sec how long will it take the bar to reach 98° c? (round your answer to one decimal place.)

Aballoon is rising vertically upwards at a velocity of 10m/s. when it is at a height of 45m from the ground, a parachute bails out from it. after 3s he opens his parachute and decelerates ata a constant rate 5m/s.when. (a) what was the height of the parachutist above the ground when he opened his parachute? (b)how far is the parachutist from the balloon at t=3s? (c)with what velocity does the parachutist hit the ground? (d)after how long does the parachutist hit the ground after his exist from the balloon?

Refer to your lab guide and review the data in table b to complete each statement. the mass of g1 + g2 after the collision kg. the velocity of g1 + g2 after the collision m/s. the momentum of the combined gliders after the collision kg · m/s.