Answer:
a. 
b. 
Explanation:
Using the triangle theorem both triangle the woman makes between the light so the rate of change of length can use geometry first

Solve to find the rate relation


Now the rate of the change rate


Finally the rate of her shadow moving


Answer:
7/150
Explanation:
The following data were obtained from the question:
Object distance (u) = 75cm
Image distance (v) = 3.5cm
Magnification (M) =..?
Magnification is simply defined as:
Magnification (M) = Image distance (v)/ object distance (u)
M = v /u
With the above formula, we can obtain the magnification of the image as follow:
M = v/u
M = 3.5/75
M = 7/150
Therefore, the magnification of the image is 7/150.
Answer:
Only a backward force is acting, no forward force.
Explanation:
- Once released from the initial push, in absence of friction, the shopping cart would continue moving forward at a constant speed forever.
- As it would move at a constant speed, no net force would be acting on it.
- So, if it is gradually slowing, there must be a net force producing an acceleration in a direction opposite to the movement.
- This force is the kinetic friction force, and is the only force acting on the cart in the horizontal direction.
- As any friction force, opposes to the relative movement between the cart and the horizontal floor, which means that is directed backward.
- This is consistent with the direction of the acceleration of the cart.