Carden

This page lists questions and answers that were posted by visitors named Carden.

Questions

The following questions were asked by visitors named Carden.

At a playground, a 18.7 kg child plays on a slide that drops through a height of 2.07 m. The child starts at rest at the top of the slide. On the way down, the slide does a nonconservative work of -318 J on the child. What is the child's speed at the bott...

Catching a wave, a 65 kg surfer starts with a speed of 1.3 m/s, drops through a height of 2.10 m, and ends with a speed of 8.2 m/s. How much nonconservative work was done on the surfer? I have genuinely no idea how to solve this problem.

The work required to stretch a certain spring from an elongation of 4.11 cm to an elongation of 5.11 cm is 32.0 J. (a) Is the work required to increase the elongation of the spring from 5.11 cm to 6.11 cm greater than, less than, or equal to 32.0 J? (b) V...

A 2.1 kg block slides with a speed of 1.1 m/s on a frictionless, horizontal surface until it encounters a spring. (a) If the block compresses the spring 5.7 cm before coming to rest, what is the force constant of the spring? (b) What initial speed should...

A 0.47 kg pendulum bob is attached to a string 1.2 m long. What is the change in the gravitational potential energy of the system as the bob swings from point A to point B where θ = 31°? I've tried using PE = mgh but I don't know where the 31 degrees come...

A child sits in a wagon with a pile of 0.60 kg rocks. If she can throw each rock with a speed of 10 m/s relative to the ground, causing the wagon to move, how many rocks must she throw per minute to maintain a constant average speed against a 3.7 N force...

The collision between a hammer and a nail can be considered to be approximately elastic. Estimate the kinetic energy acquired by a 13 g nail when it is struck by a 550 g hammer moving with an initial speed of 4.1 m/s. I am completely confused by this prob...

Answers

The following answers were posted by visitors named Carden.

I'm still confused. How does that equal 1/2mv2 and how does that solve the problem.

1) my teacher is really bad. 2) Is delta potential energy = mgvf - mgvi

thank you, I got it

I HAVE THE ANSWER. THANK YOU

Thank you, I understand that now.

That's why I was getting it wrong. I kept using delta x which was one in both cases. Have I mentioned you are a lifeseaver.

KE initial = 0 PE initial = mgh = 68.8662 = KE final KE final = 1/2mv2 v = 23.01 That isn't right. What have I done wrong?

I am just so confused by this problem. I have done other problems with ease and I'm having so much trouble with other ones.

I got KE = 4.622 J and it isn't correct

I did m1v1 /(m1+m2) = vf = .252723 x = vf(m/k) x = .366

x = v * sqrt(m/k) correct?

when I set 1/2mv2 equal to 1/2kx2 I got .366