<span>A 67.0 kg crate is being raised by means of a rope. Its upward acceleration is 3.50 m/s2. What is the force exerted by the rope on the crate?
</span>Newton's Second Law<span> of Motion states, “The force acting on an object is equal to the mass of that object times its acceleration.” We calculate as follows:
</span>
F = ma = 67.0 kg (3.50 m/s^2) = 234.5 J
Explanation:
Acceleration of an object is calculated by finding the change in its velocity divided by time taken.
If
is initial velocity,
is final velocity and t is time taken. Then the acceleration of the object is given by :
.....(1)
So, the above equation is used to find acceleration. It is called the first equation of motion. After rearranging equation (1), the correct options are :




Answer:
<em>Second option</em>
Explanation:
<u>Linear Momentum</u>
The linear momentum of an object of mass m and speed v is
P=mv
If two or more objects are interacting in the same axis, the total momentum is

Where the speeds must be signed according to a fixed reference
The images show a cart of mass 2m moves to the left with speed v since our reference is positive to the right

The second cart of mass m goes to the right at a speed v

The total momentum before the impact is

The total momentum after the collision is negative, both carts will join and go to the left side
The first option shows both carts with the same momentum before the collision and therefore, zero momentum after. It's not correct as we have already proven
The third option shows the 2m cart has a positive greater momentum than the other one. We have proven the 2m car has negative momentum. This option is not correct either
The fourth option shows the two carts keep separated after the collision, which contradicts the condition of the question regarding "they hook together".
The second option is the correct one because the mass
has a negative momentum and then the sum of both masses keeps being negative
To solve this problem it is necessary to apply the concepts related to Malus' law. Malus' law indicates that the intensity of a linearly polarized ray of light that passes through a perfect analyzer with a vertical optical axis is equivalent to:

Indicates the intensity of the light before passing through the Polarizer,
I = The resulting intensity, and
= Indicates the angle between the axis of the analyzer and the polarization axis of the incident light.
There is 3 polarizer, then
For the exit of the first polarizer we have that the intensity is,

For the third polarizer then we have,

Replacing with the first equation,



Therefore the transmitted intensity now is
of the initial intensity.
Answer:
d) the amount of work is the same whether the bag is moved all at once or in two stages, provided the total height lifted is the same in either case.
Explanation:
While moving the bag to the shelf in one shot we can say that the total work done is given as

here we know that
2H = total height raised by the bag
now when we raise the bag to first shelf and then move it to next shelf
then we will have
![W = W_1 + W_2[tex][tex]W = mgH + mgH](https://tex.z-dn.net/?f=W%20%3D%20W_1%20%2B%20W_2%5Btex%5D%3C%2Fp%3E%3Cp%3E%5Btex%5DW%20%3D%20mgH%20%2B%20mgH)

so the correct answer will be
d) the amount of work is the same whether the bag is moved all at once or in two stages, provided the total height lifted is the same in either case.