Answer:
A:- 50 J
B:- 500 J
Explanation:
a) Given that a 25 N force is applied to move the box. Also the floor is having friction surface.
So in order to move the box, the floor should have friction of atleast 25 N.
∴ friction = 25 N
Work done = force * displacement of box
Given, the box is moved 2 m across the floor
So, Work done = friction * 2 m
= 25 * 2
= 50 J
b) Given, the box is having weight of 250 N weight
Gravitational force is acting on the box which is equal to (mass * gravity)
∴ Force = 250 N
The box is lifted 2 m above the floor.
So, displacement = 2 m
Work done = force * displacement of box
Work done = 250 * 2
= 500 J
Answer:
(iv), (v), (vi) would be incorrect.
Explanation:
(iv) Force isn't transferred from one colliding object to another, but momentum can be.
(v) An object doesn't stop immediately a force stops acting on it. Think of a thrown ball.
(vi) For an object not to move, it means that the net force on the object is zero, and not necessarily that there are no forces acting on the object. For example, an object could be pushed on one side, and be pushed on the other side with an equal force in the opposite direction. The forces would cancel each other and the net force would be zero.
The rest should be correct.
Answer:
8.46 N/C
Explanation:
Using Gauss law

Gauss's Law states that the electric flux through a surface is proportional to the net charge in the surface, and that the electric field E of a point charge Q at a distance r from the charge
Here, K is Coulomb's constant whose value is 
r = 0.43 + 0.106 = 0.536 m

Answer:
It controls the amount of current.
Explanation:
A resistor helps control and maintain the circuit which is it's main function.
The value of change in kinetic energy, ΔEk when a cart is being pulled forward by a hanging mass is Positive
In order words, ΔEk in the above question is positive
<h3>What is kinetic energy?</h3>
Kinetic energy can be defined as the energy a body possess when the body is in motion or due its motion
In conclusion, the value of change in kinetic energy, ΔEk when a cart is being pulled forward by a hanging mass is Positive
Learn more about kinetic energy:
brainly.com/question/25959744
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