NOTE: Please draw a free body diagram/ visual representation before solving the

Question

NOTE: Please draw a free body diagram/ visual representation before solving the question. You are at the state fair with your friends. While walking through the Midway, you see a game where the prize is a big stuffed Scottie dog. This game uses a big glass puck that gets slid up a glass ramp and that needs to go through a hole. The puck has a radius of about 7 cm, and it looks like the hole has a radius of only 8 cm - so your aim has to be very good. The ramp has an angle of 10, and it is 3.5 meters between where you push the puck and the hole. The puck is pretty heavy, at 1.9 kg, but you manage to give it an initial speed of 8.6 m/s. Do you get to take home the Scottie dog?

NOTE: The 3.5 meters 'between where you push the puck and the hole' is the inclined distance up the ramp not parallel to the ground. Also, the puck wont go through the hole if it flys past it. Also, also, glass does not mean frictionless.

Explanation / Answer

for a mass on incline with frictional force acting on it,

Fnet = ma = mg sin(theta) - u mg cos(theta)

a = g [sin(theta) - u cos(theta)] = 9.81 [sin10 - 0.4 x cos10] = -2.16 m/s^2

from eqn of motion, the distance that the puck can move with the given speed will be:

v^2 = u^2 + 2 a s

s = 8.6^2/2 x 2.16 = 17.12 m

I conlcude that the velocity intially given to the puck is more than the required velocity for entering the hole hence it will pass over the hole and you will not win the Scottie dog.

Related Questions

Navigate

• Browse (All)
• Browse N
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.