Answer:
Explanation:
Remark
This is a second class lever. It is much more efficient than the fishing pole problem. All distances are measured from the pivot in these kinds of questions.
Givens
d1 = 1.5
d2 = ?
m1 = 50 kg
m2 = 30 kg
The lighter child will have to sit further away from the pivot to make the two conditions equal.
Formula
d1*m1 = d2*m2
1.5*50 = d2 * 30
75 = 30 * d2
75/30 = d2
d2 = 2.5
Remark
Notice that the distance is longer for the lighter child. The fact that these are masses and not forces does not matter, but you should take note of it. There is a difference between masses and forces. See the fishing pole problem.
Answer to the multiple Choice question. No motion on this kind of problem means equal moments. The answer is D
Problem 2
1) The wheels are further apart making B more stable. The wider the distance the wheels are apart, the harder it would be to tip the concrete mixer over
2) The center of gravity is lower. The higher the force is the more chance you have of exerting an external force to tip the mixer over.
Gravitational acceleration is approx 9.8 m/s
Time is 7s
a=9.8 m/s
t=7s
a = d/t^2
therefore:
d = a * t^2
d = 9.8 * 7^2
d = 9.8 * 49
d = 480.2 [m]
Step-#1:
Ignore the wire on the right.
Find the strength and direction of the magnetic field at P,
caused by the wire on the left, 0.04m away, carrying 5.0A
of current upward.
Write it down.
Step #2:
Now, ignore the wire on the left.
Find the strength and direction of the magnetic field at P,
caused by the wire on the right, 0.04m away, carrying 8.0A
of current downward.
Write it down.
Step #3:
Take the two sets of magnitude and direction that you wrote down
and ADD them.
The total magnetic field at P is the SUM of (the field due to the left wire)
PLUS (the field due to the right wire).
So just calculate them separately, then addum up.
The answer is parallel
If the <span>circuits in a car</span> were series, they would go out at the same time.
I hope this helps! :3
