Posted by **Jacob** on Monday, April 12, 2010 at 11:55pm.

A student throws a 9 gram of gum is thrown across the physics lab from a distance of 2.5 m. When the gum has a horizontal velocity of vo it connects with a mass on the end of 1.62 kg simple pendulum which is initially at rest. The pendulum has a length of L of 0.74 m. The gum sticks to the pendulum mass and swings backwards to gain a vertical height of 12.7 cm.

(a) What is initial velocity of the wad of gum?

vmax = ?

i used the formula 2pi (l/g)squareroot then 2pi/T to get the w and timed it by Amp but i still didnt get it right

- physics -
**drwls**, Tuesday, April 13, 2010 at 8:17am
You don't need the period of the pendulum (or the pendulum length) to do this problem. The vertical height H that the pendulum rises tells you the velocity the pendulum (mass M) and gum (mass m) acquire right after the collision. Call that velocity V.

V = sqrt (2 g H)= 1.58 m/s

Now apply conservation of momentum to the impact-and-sticking process (before the pendulum has swung at all). Let vo be the velocity of the gum before impact.

m vo = (M+m)V = (M+m)sqrt(2gH)

Solve for vo.

vo = (1.629/0.009)*1.58 m/s

286 m/s

I don't think gum can be thrown that fast. It is nearly the speed of sound. However, the method seems correct to me. I believe that unrealistic numbers have been provided

## Answer this Question

## Related Questions

- math ms sue please help, PLEASE!!!! - tori had 20 gumballs in a bag. there were ...
- Statistics - A recent study stated that if a person chewed gum the average ...
- Physics - A piece of gum comes lose from underneath an elevator that is moving ...
- math advanced functions - Canada’s Wonderland has a roller coaster named ‘...
- Math - Jackson wnats to give everyone in his class (including himself) 1 piece ...
- Math - There are 9 red gum balls, 5 green gum balls, 8 yellow gum balls, and 8 ...
- algebra - a factory just outside of newyork city produces 40 packs of gum in 4.2...
- physics-circular motion - the turntable of a record player rotates at a rate of ...
- math - PLEASE HELP!!!(: There are 9 red gum balls, 5 green gum balls, 8 yellow ...
- math - There are 9 red gum balls, 5 green gum balls, 8 yellow gum balls, and 8 ...

More Related Questions