Gravitational potential energy is related to–A. what an object is made of. B.an object’s motion.C. an object’s position.D. an ob
1 answer:
You might be interested in
Answer:
Explanation:
We have the following data:
- distance covered by the child: d = 2 m (length of the slide)
- time taken to cover this distance: t = 3 s
- initial velocity of the child: 0 m/s (he starts from rest)
So we can find the acceleration by using the equation:
Where a is the acceleration.
Substituting the values and solving for a,
Answer:
6.57 m/s
Explanation:
First use Hook's Law to determine the F the compressed spring acts on the mass. Hook's Law F=kx; F=force, k=stiffnes of spring (or spring constant), x=displacement
F=kx; F=180(.3) = 54 N
Next from Newton's second law find the acceleration of the mass.
Newton's .2nd law F=ma; a=F/m ; a=54/.75 = 72m/s²
Now use the kinematic equation for velocity (or speed)
v₂²= v₀² + 2a(x₂-x₀); v₂=final velocity; v₀=initial velocity; a=acceleration; x₂=final displacement; x₀=initial displacment.
v₀=0, since the mass is at rest before we release it
a=72 m/s² (from above)
x₀=0 as the start position already compressed
x₂=0.3m (this puts the spring back to it's natural length)
v₂²= 0 + 2(72)(0.3) = 43.2 m²/s²
v₂= = 6.57 m/s