# Bat hits baseball

• gnome222

#### gnome222

<< Moderator Note -- thread moved to the HH forums >>

a pitcher throws a 1.5kg baseball with speed 25m/s. it hits the bat and return in opposite direction with same speed. the force that bat exerted on ball is 50N. For how long was the bat touching(in contact) the ball? I used: delat t * F = m*delta velocity delta t 50N = 1.5(25-(-25)) and i got t=1.5 s. Is it correct? It does not seem like.

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a pitcher throws a 1.5kg baseball with speed 25m/s. it hits the bat and return in opposite direction with same speed. the force that bat exerted on ball is 50N. For how long was the bat touching(in contact) the ball? I used: delat t * F = m*delta velocity delta t 50N = 1.5(25-(-25)) and i got t=1.5 s. Is it correct? It does not seem like.
That's a pretty happy baseball. Are you sure of that 1.5 kg?

Chet

That's a pretty happy baseball. Are you sure of that 1.5 kg?

Chet
yes

yes
A major league baseball has a mass of 5.25 oz (0.15 kg). That 1.5 kg is an obvious typo.

And, please, don't try to play baseball with a 1.5 kg baseball. If you got hit by a fastball, it would be "lights out."

Chet

o
A major league baseball has a mass of 5.25 oz (0.15 kg). That 1.5 kg is an obvious typo.

And, please, don't try to play baseball with a 1.5 kg baseball. If you got hit by a fastball, it would be "lights out."

Chet
ok, but under the conditions described what would be time?

o

ok, but under the conditions described what would be time?
If you are asking whether you solved the problem correctly, given the obviously faulty data, then the answer is yes.

Chet

force is the rate of change of momentum.
Thus, you have been given the change in momentum, the force excerted.
So,
t=Change in momentum/force
=2*1.5*25/50=75/50=1.5