(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

1.A block is sent up a frictionless ramp along which an x axis extends upward. The figure below gives the kinetic energy of the block as a function of position x; the scale of the figure's vertical axis is set by Ks = 38.0 J. If the block's initial speed is 4.70 m/s, what is the normal force on the block?

2. A startled armadillo leaps upward rising 0.553 m in the first 0.197 s.

(a) What is its initial speed as it leaves the ground?

Correct: Your answer is correct. m/s

(b) What is its speed at the height of 0.553 m?

Correct: Your answer is correct. m/s

(c) How much higher does it go?

2. Relevant equations

F=ma

v^2=v0^2+2ad

3. The attempt at a solution

For the first question

KE=.5mv^2

152 J = .5m(4.70 m/s)^2

m=13.8 kg

Height of the ramp

.5mv^2=mgh

152 J=13.8kg*9.8m/s^2*h

h=1.13 m

Solve for the angle of the ramp

sin-1(1.13m/2m) = 34 deg

N-mgcos34=0

N=13.8*9.8cos34=111 N. But this is wrong.

2nd question...

solved pt a and b, got 3.77 m/s for v0, 1.84 m/s vf

v0 is 0 m/s at the top of the height, so

0=3.77m/s ^2 +2*9.8m/s^2d

solve for d, get .725

difference is .17 m. But this is wrong.

Thank you so much! Final monday and I have a C-:/

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# Homework Help: Kinematics and also an energy

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