Answer:
Before the plank will tip cat will walk 1.652 m
Explanation:
Mass of the cat along with plank 
Center of mass of the plank 
Mass of cat 
We have to find how far right of sawhorse B.
Plank will tip when weight of the cat about B is greater than the torque by the weight of the plank.
Balancing the the torque



D is the amount of space object takes up
Answer:
It cancels recoil.
Explanation:
For each action there is an equal an opposite reaction.
The principle of conservation of momentum tell us that if a single spore were ejected the fern would suffer a recoil from it. This recoil would take energy and speed from the spore. But if they are ejected in pairs the recoil is canceled and all the energy is transferred to the spores resulting in higher speeds.
Answer:
N = 195 turns
Explanation:
The inductance of the inductor, L = 500 μH = 500 * 10⁻⁶H
The length of the tube, l = 12 cm = 0.12 m
The diameter of the tube, d = 4 cm = 0.04 m
Radius, r = 0.04/2 = 0.02 m
Area of the tube, A = πr² = 0.02²π = 0.0004π m²

The inductance of a solenoid is given by:


Recall that

where
and
are the initial and final velocities, respecitvely;
is the acceleration; and
is the change in position.
So we have


(Normally, this equation has two solutions, but we omit the negative one because the car is moving in one direction.)