The mass of an object always stays the same since it is really just the amount of matter in an object so no matter the force applied, as long as the object does not lose or gain matter, the object stays the same
B is you answer sorry i dont quite know how to explain it in a way that you and anybody else would understand it.
Answer:
The focal length of the mirror is 52.5 cm.
Explanation:
Given that,
Object to Image distance d = 140 cm
Image distance v= 35 cm
We need to calculate the object distance


We need to calculate the focal length
Using formula of mirror

Put the value into the formula



Hence, The focal length of the mirror is 52.5 cm.
This is a very wierd question but I will answer.It is A
Hope I helped
The force of friction is 78.4 N
What is force of friction?
Frictional force is the force created when two surfaces come into contact and slide against each other. it is given by the equation:
μ * 
where,
= force of friction
μ = coefficient of friction
= normal force
Given,
μ 
We know,


Subsituing the values in equation:
μ * 

The force of friction is 78.4 N.
To know more about force of friction, check out:
brainly.com/question/24386803
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