We can solve the problem by using conservation of momentum.
The player + ball system is an isolated system (there is no net force on it), therefore the total momentum must be conserved. Assuming the player is initially at rest with the ball, the total initial momentum is zero:
The total final momentum is:
where 
is the momentum of the player and 
is the momentum of the ball.
The momentum of the ball is: 
While the momentum of the player is: 
, where M=59 kg is the player's mass and vp is his velocity. Since momentum must be conserved,
so we can write
and we find
and the negative sign means that it is in the opposite direction of the ball.
Answer:
V = L A = L pi R^2 volume of wire
V = 50 cm * .01 cm^2 = .5 cm^3
d(density) = 3.5 gm / .5 cm^3 = 7.0 gm/cm^3
A micrometer caliper could measure the diameter of the wire.
Answer:
<u>The car's average speed is 32 kilometers per hour</u>
Explanation:
1. Let's review the information given to us to answer the question correctly:
First two hours = 60 kilometers
Next two hours = 68 kilometers
2. What is the car's average speed?
Total distance traveled by the car = 60 + 68
Total distance traveled by the car = 128
Total time of travel = 2 + 2 hours
Total time of travel = 4 hours
Average speed = Total distance/Total time
Replacing with the real values, we have:
Average speed = 128/4
<u>Average speed = 32 kilometers per hour</u>
<span>PV = nRT
moles of H2 = 1/2 = 0.5
moles of He = 1/4 =0.25
T = 273 + 27
partial pressure of H2
Px1 = 0.5x0.083x300
P=12.45 atmospheres
PP of He
px1 = 0.25x0.083x300
P =6 22 atmospheres
Totla pressure = 6.22 + 12.45 = 18.68 atm</span>
