2. May (75 kg) and Amber (49 kg) stand motionless on ice skates, facing each other at arm's length on a smooth,
frozen pond. Which of the following actions will give Amber the least speed?
a) Amber pushes May with 500 N of force for 0.1 s.
b) Amber pushes May with 800 N of force for 0,08 s.
c) Amber pushes May with 600 N of force for 0,04 s.
d) May pushes Amber with 100 N of force for 0,6 s.
c) May pushes Amber with 300 N of force for 0.2 s.

the velocity you are looking for is made up of two parts: horizontally velocity, vh, and its vertical velocity, vv. the actual velocity of the ball will be these two parts added together, and because velocity is a vector then they will need to be added vectorially.  

neglecting air resistance etc etc.,  

the horizontal velocity component will be constant (because there is no accelerating force in the horizontal direction.  

vh = 8 ms-1  

the vertical velocity component has an accelerating force: 'g'.  

using v = u +at where a = g = 9.81 ms-2.  

the vertical component of velocity, vv = 0 + gt = vv =9.81 x 2  

vv = 19.62 ms-1 . the zero appears because the virtical component of velocity at time t=0 is zero. remember, the ball was thrown horizontally.  

how fast it will be moving (it actual path (being a parabola )) will be the vector sum of these two.  

adding vectorally gives: -  

v = sqr root (8^2 + 19.62^2) = sqr root(64+384.9) = 21.18 or 21.2 ms-1

b.transmitters send radio waves, and receivers capture radio waves.

1 the 4 is sig