Force is used to put things in motion you can’t have motion without force!
Even if it just pushing a piece of paper you still use force to put the paper in motion!
We Know, W = F * s
here, F = 25 N
s = 3 m
Substitute it into the expression,
W = 25 * 3
W = 75 Joule
So, your final answer is 75 J
Hope this helps!
Answer:
a

b

Explanation:
From the question we are told that
The mass of the person is 
The speed of the person is 
The energy of the proton is 
Generally the de Broglie wavelength is mathematically represented as

Here h is the Planck constant with the value

So

=> 
Generally the energy of the proton is mathematically represented as

Here
is the mass of proton with value 
=> 
=> 
=> 
So

so 
=> 
let here North direction is along +Y and South direction is along -Y
similarly East direction is towards +X and west direction is towards -X
now it is given that
first it moves 235 km north

then it moves back 126 km south

then again he moves north

now the total displacement is given as


so final displacement of train is 154 km North