Answer:

Work done to bring three electrons from a great distance apart to 3.0×10−10 m from one another (at the corners of an equilateral triangle) is 
Explanation:
The potential energy is given by:
U=Q*V
where:
Q is the charge
V is the potential difference
Potential Difference=V=
So,

Where:
k is Coulomb Constant=
q is the charge on electron=
r is the distance=
For 3 Electrons Potential Energy or work Done is:


Work done to bring three electrons from a great distance apart to 3.0×10−10 m from one another (at the corners of an equilateral triangle) is 
Because: Some of the work done by the machine is used to overcome the friction created by the use of the machine. ... Work output can never be greater than work input. Machines allow force to be applied over a greater distance, which means that less force will be needed for the same amount of work.
Answer:
the length of the simple pendulum is 0.25 m.
Explanation:
Given;
mass of the air-track glider, m = 0.25 kg
spring constant, k = 9.75 N/m
let the length of the simple pendulum = L
let the frequency of the air-track glider which is equal to frequency of simple pendulum = F
The oscillation frequency of air-track glider is calculated as;

The frequency of the simple pendulum is given as;

Thus, the length of the simple pendulum is 0.25 m.
Answer:
The acceleration is 1 cm/s^2.
Explanation:
The acceleration is defined as the rate of change of velocity.
Here, initial velocity, u = 3/1 = 3 cm/s
final velocity, v = 4/1 = 4 cm/s
time, t = 1 s
Let the acceleration is a.
Use first equation of motion
v = u + at
4 = 3 + 1 x a
a = 1 cm/s^2
Answer:
1. 310 N
2. 310 N
Explanation:
1. Determination of the net force.
Force applied (Fₐ) = 430 N
Force experience (Fₑ) = 120 N
Net force (Fₙ) =?
Fₙ = Fₐ – Fₑ
Fₙ = 430 – 120
Fₙ = 310 N
Hence, the net force acting on the crate is 310 N
2. Determination of the net force.
Force applied (Fₐ) = 375 N
Force of friction (Fբ) = 65 N
Net force (Fₙ) =?
Fₙ = Fₐ – Fբ
Fₙ = 375 – 65
Fₙ = 310 N
Hence, the net force acting on the crate is 310 N.