Answer:
It will take 8.80 sec to fall from the building
Explanation:
We have given height pf the state building h = 380 m
Initial velocity will be 0 m /sec
So u = 0 m/sec
Acceleration due to gravity
We have to find the fall time
According to second equation of motion
So
t = 8.80 sec
Answer:
energy left over from the big bang
Explanation:
Answer:
The total energy of the object does not change is the true statement.
Explanation:
1. The force applied to the object is perpendicular to the movement so doesn't work on it, assuming the table is at the same height in all of its points the only energy we have to analyze is the kinetic energy , because the table top is frictionless by Newton's first law the velocity (v) doesn't change so the kinetic energy is constant and the total energy too.
2. There's no friction in this situation
3. As stated on 1. because the applied force is perpendicular to the movement of the object, there force doesn't work on it.
4. There are over one force on the object, the weight and the normal force table top exerts to the object.
So the only true statement is 1.
Answer:
Graph C
Explanation:
This is the answer because it is the only one that shows the vehicle accelerate to a constant speed before stopping and slowing down.
Answer:
Explanation:
When the spring is compressed by .80 m , restoring force by spring on block
= 130 x .80
= 104 N , acting away from wall
External force = 82 N , acting towards wall
Force of friction acting towards wall = μmg
= .4 x 4 x 9.8
= 15.68 N
Net force away from wall
= 104 -15.68 - 82
= 6.32 N
Acceleration
= 6.32 / 4
= 1.58 m / s²
It will be away from wall
Energy released by compressed spring = 1/2 k x²
= .5 x 130 x .8²
= 41.6 J
Energy lost in friction
= μmg x .8
= .4 x 4 x 9.8 x .8
= 12.544 J
Energy available to block
= 41.6 - 12.544 J
= 29 J
Kinetic energy of block = 29
1/2 x 4 x v² = 29
v = 3.8 m / s
This will b speed of block as soon as spring relaxes. (x = 0 )