So the answer is B) he should wire each room in parallel. This is because when the bulbs are in parallel if one part of the parallel circuit is broken (eg when you switch a light off) then the current can still flow to all the other bulbs, meaning they stay turned on. Hope this helps :)
A parachute increases air friction, thus reducing falling speed.
Indeed, the air friction is roughly proportional to the surface of the object falling down; the parachute tremendously increases that surface.
Answer:
-2200 N
Explanation:
The change in momentum of Sarah is equal to the impulse, which is the product between the force exerted by the seatbelt on Sarah and the time during which the force is applied:
where
m is the mass
is the change in velocity
F is the average force
is the duration of the collision
In this problem:, we have:
m = 55 kg is Sarah's mass
is the change in velocity
is the duration of the collision
Solving for F, we find the force exerted by the seatbelt on Sarah:
Where the negative sign indicates that the direction of the force is opposite to that of Sarah's initial velocity.