A) From rest and before performing the described exercise, the entire weight of the desk is supported by the floor. This support force (normal force) exerted by the floor will be equivalent to the force equivalent to the weight of the desk. From the moment the desk starts to be lifted, said support force will decrease and the weight of the desk supported by the floor will be less.
B) As the desk is lifted, the support force of the two guests will increase, this occurs because the force is transferred to the support of both, but the support force of the floor on the two people will increase.
The speed of the 0.8 kg ball immediately after collision is 0.625 m/s in opposite direction to the stationary ball.
The given parameters;
- mass of the ball, m₁ = 0.8 kg
- speed of the ball, u₁ = 2.5 m/s
- mass of the object at rest, m₂ = 2.5 kg
- final velocity of the object at rest, v₂ = 1 m/s
Let the final velocity of the 0.8 kg ball immediately after collision = v₁
Apply the principle of conservation of linear momentum;
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂
(0.8 x 2.5) + (2.5 x 0) = (0.8)v₁ + 2.5(1)
2 = 2.5 + (0.8)v₁
-0.5 = (0.8)v₁
Thus, the speed of the 0.8 kg ball immediately after collision is 0.625 m/s in opposite direction to the stationary ball.
Learn more here: brainly.com/question/7694106
Answer:
The value is 
Explanation:
From the question we are told that
The mass of the bullet is 
The mass of the wood is 
The height attained by the combined mass is 
Generally according to the law of energy conservation
Here 
is the kinetic energy of the bullet before collision.
and 
is the potential energy of the combined mass of bullet and wood at the height h which is mathematically represented as
![PE_m = [m_b + m_w] * g * h](https://tex.z-dn.net/?f=PE_m%20%20%3D%20%20%5Bm_b%20%20%2B%20m_w%5D%20%2A%20%20g%20%2A%20%20h)
So
![KE_b =PE_c = [0.005 + 0.90] * 9.8 *0.08](https://tex.z-dn.net/?f=KE_b%20%3DPE_c%20%20%20%3D%20%5B0.005%20%20%2B%200.90%5D%20%2A%209.8%20%2A0.08)
=>
Total amount of energy would remain constant according to law of conservation of energy. i.e., 50 Joules
In short, Your Answer would be Option C) <span>50 Joules because as energy converts from one form to another, it cannot be created or destroyed during the conversion.
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Hope this helps!
Answer:
Claim: The heart pumps more blood throughout the body when one exercises because exercise takes a lot of energy from the body.
Evidence: Heart rate went from 80 bpm to 120 bpm
Reasoning: Doing exercise takes a lot of energy to do, causing the circulatory system to have to work harder and pump more blood throughout the body in order to allow someone to be able to do a task that involves so much movement and energy.
Explanation:
