kmag
- 1
- 0
I feel so confused right now, I'm probably over thinking this though. Please help!
1) A slingshot consists of a light leather cup, containing a stone, that is pulled back against two parallel rubber bands. It takes a force of 11 N to stretch either one of these bands 1.1 cm.
(a) What is the potential energy stored in the two bands together when a stone is placed in the cup and pulled back 0.19 m from the equilibrium position?
Round your answer to two significant figures.
(b) With what speed does the stone leave the slingshot?
Round your answer to two significant figures.
2) A child's toy consists of a piece of plastic attached to a spring in the following figure. The spring is compressed against the floor a distance of 2.05 cm, and the toy is released. If the toy has a mass of and rises to a maximum height of 57.0 cm, estimate the force constant of the spring.
Note: the height of the toy in a compressed state is negligible in comparison with the maximum height.
Round your answer to three significant figures. Take the free fall acceleration to be .
I've already tried using the equations F= kx and Us=1/2kx^2 but I'm not getting the right answer. I filled F in with 11 N and x with 0.011 m to find k, I got 1000. Then I plugged 1000 into the other equation and got 1/2(1000)(0.19^2). I got 18.05 and rounded to two sig figs 18 but it is still not right. What am I doing wrong? Please help!
1) A slingshot consists of a light leather cup, containing a stone, that is pulled back against two parallel rubber bands. It takes a force of 11 N to stretch either one of these bands 1.1 cm.
(a) What is the potential energy stored in the two bands together when a stone is placed in the cup and pulled back 0.19 m from the equilibrium position?
Round your answer to two significant figures.
(b) With what speed does the stone leave the slingshot?
Round your answer to two significant figures.
2) A child's toy consists of a piece of plastic attached to a spring in the following figure. The spring is compressed against the floor a distance of 2.05 cm, and the toy is released. If the toy has a mass of and rises to a maximum height of 57.0 cm, estimate the force constant of the spring.
Note: the height of the toy in a compressed state is negligible in comparison with the maximum height.
Round your answer to three significant figures. Take the free fall acceleration to be .
I've already tried using the equations F= kx and Us=1/2kx^2 but I'm not getting the right answer. I filled F in with 11 N and x with 0.011 m to find k, I got 1000. Then I plugged 1000 into the other equation and got 1/2(1000)(0.19^2). I got 18.05 and rounded to two sig figs 18 but it is still not right. What am I doing wrong? Please help!