Explanation:
Given that,
Weight of the friend, W = 600 N
When the friend sits on the metal frame it bends downward 4 cm, we can say that the compression in the it is 4 cm or 0.04 m
To find,
Spring constant for this chair or k
Solve :
The weight of an object is equal to the force exerted by the gravitational force, F = 600 N
According to Hooke's law, the force exerted by the spring is given by :
F = kx
k is the spring constant


k = 15000 N/m
Therefore, the spring constant of the spring is 15000 N/m.
This is Kinematics and the equations in your book.
A speed time graph would plot the speed of something against the teime it was at a speed.
If it were changing it speed constantly, that would be a straight line if acclerating. Total distrance would be the area under the graph.
Newton's second law of motion describes what happens to a body when an external force is applied to it.
Newton's second law of motion states that the force acting on an object is equal to the mass of that object times its acceleration. In mathematical form this is written as
F = ma
Where F is force , m is mass and a is acceleration. The math or logic behind this is that if you double the force, you double the acceleration, but if you double the mass, you cut the acceleration in half.
Answer:
The sphere is positively charged
Explanation:
This is because when the positively charged rod is brought near the metal rod A, the electrons in metal rod A and sphere B are attracted towards it into metal rod A while the positive charges in the are repelled into sphere B. So, when the charged rod is withdrawn, and metal rod A and sphere B are separated, metal rod A is now negatively charged, but sphere B is positively charged.
So, sphere B is positively charged.