Explanation:
(c) I assume we're looking for mA.
Sum of forces on B in the -y direction:
∑F = ma
mBg − T = mBa
Sum of forces on A in the +x direction:
∑F = ma
T = mAa
Substitute:
mBg − mAa = mBa
mBg − mBa = mAa
mA = mB (g − a) / a
Plug in values:
mA = (5 kg) (10 m/s² − 0.01 (10 m/s²)) / (0.01 (10 m/s²))
mA = 495 kg
The answer key seems to have a mistake. It's possible they meant mB = 1 kg, or they changed mB to 5 kg but forgot to change the answer.
Assuming the power delivered by the horse does not change, the speed of the cart will decrease.
In fact, the power delivered by the horse is the work done by the horse (W) per unit time (t):

<span>If several bags are added to the cart, the horse must do more work to transport them. Therefore, W in the fraction increases. But if the power P of the horse is constant, then it means that the time t must increase as well. So, the horse will take more time to transport the car, and this means that the speed of the cart has decreased.</span>
The easiest way I know to explain it is this:
-- Take a flashlight and a ball into a dark room.
-- Turn on the flashlight and point it at the ball.
-- Half of the ball is lighted up by the flashlight, and the other half is dark.
-- There is no way you can turn or twist the ball to make more or less
than 50% of it lighted up and more or less than 50% of it dark.
<em>Everything</em> in the solar system ... as long as it's shaped like a ball ... is
half illuminated by the sun and half dark.
Resistance in wires causes thermal energy. The correct
answer between all the choices given is the third choice or letter C. I am
hoping that this answer has satisfied your query and it will be able to help
you in your endeavor, and if you would like, feel free to ask another question.
Answer:
It will be easier to break the meter rule with the long side against my knee.
Explanation:
To break the meter rule involves the principle of bending moment. The long side will require less force to generate the same amount of bending moment that will have to be generated to break the meter rule. The short side on the other hand will require more force to generate this mount of bending moment. This is because the shorter has a very small surface area, which concentrates the force on your knee. The pressure is then dissipated as more pressure to your knee. Th longer side has a lesser surface area so, most of the force is used in breaking the meter rule.