The first law of thermodynamics states that the change U in the internal energy of a system is given by U Q W, where Q is the he
1 answer:
You might be interested in
Answer:
ΔK = 2.45 J
Explanation:
a) Using the law of the conservation of the linear momentum:
Where:
Now:
Where is the mass of the car,
is the initial velocity of the car,
is the mass of train,
is the final velocity of the car and
is the final velocity of the train.
Replacing data:
Solving for :
Changed to cm/s, we get:
b) The kinetic energy K is calculated as:
K =
where M is the mass and V is the velocity.
So, the initial K is:
And the final K is:
Finally, the change in the total kinetic energy is:
ΔK = Kf - Ki = 22.06 - 19.61 = 2.45 J
Answer:
a
b
Explanation:
From the question we are told that
The mass of the rock is
The length of the small object from the rock is
The length of the small object from the branch
An image representing this lever set-up is shown on the first uploaded image
Here the small object acts as a fulcrum
The force exerted by the weight of the rock is mathematically evaluated as
substituting values
So at equilibrium the sum of the moment about the fulcrum is mathematically represented as
Here is very small so
and
Hence
=>
substituting values
The mechanical advantage is mathematically evaluated as
substituting values
