Answer:
Explanation:
Impulse = change in momentum
mv - mu , v and u are final and initial velocity during impact at surface
For downward motion of baseball
v² = u² + 2gh₁
= 2 x 9.8 x 2.25
v = 6.64 m / s
It becomes initial velocity during impact .
For body going upwards
v² = u² - 2gh₂
u² = 2 x 9.8 x 1.38
u = 5.2 m / s
This becomes final velocity after impact
change in momentum
m ( final velocity - initial velocity )
.49 ( 5.2 - 6.64 )
= .7056 N.s.
Impulse by floor in upward direction
= .7056 N.s
Answer:
Explanation:
It is given that three cars has same mass m with speed
suppose rest two cars also has same mass m
As there is no external force therefore momentum is conserved
Initial Momentum 
Final momentum 
where v=final velocity
thus final velocity is
Answer:
C
Explanation:
If the arrows represent light rays, then Rachel sees a candle flame when the light released by the flame is received by her eyes.
<span>If you think about it, changing the scale to which something is measured does not affect the repeatability of the measurement. For instance, if you have a meter stick which was labeled incorrectly, that doesn't affect the fact that every measurement you take of a certain fixed distance will still be the same. Precision does not equal accuracy.</span>
