Answer:
Option (c) Acceleration is 1/2x the original acceleration
Explanation:
To know the the correct answer to the question, we shall determine the acceleration of the box in each case.
Case 1:
Mass (m) = m
Force (F) = 20 N
Acceleration 1 (a₁) =?
F = ma₁
20 = m × a₁
Divide both side by m
a₁ = 20 / m
Case 2:
Mass (m) = 2m
Force (F) = 20 N
Acceleration 2 (a₂) =?
F = ma₂
20 = 2m × a₂
Divide both side by 2m
a₂ = 20 / 2m
a₂ = 10 / m
Finally, we shall determine the acceleration of the box after the mass was doubled. This can be obtained as illustrated below:
Acceleration 1 (a₁) = 20 / m
Acceleration 2 (a₂) = 10 / m
a₂ : a₁ = 10 / m : 20 / m
a₂ / a₁ = 10 / m ÷ 20 / m
a₂ / a₁ = (10 / m) × (m / 20)
a₂ / a₁ = ½
Cross multiply
a₂ = ½a₁
Thus, the acceleration of the box after the mass was doubled is ½ times the original acceleration.
Answer : (A) A charged object is brought near a neutral object without touching it.
Explanation:
Bodies can be charged by the method of conduction. By conduction the body acquires the same charge as on the charging body.
Charging the body can be understood by the following example of charging a paper cylinder by conduction. Make a paper cylinder by rolling a strip of paper on a pencil and then gently pulling out the pencil. Suspend the paper cylinder by a string tied to its center, now touch the paper cylinder with a glass rod rubbed with silk so it has a positive charge. Remove the class rod and the again bring it near to the paper cylinder.
The paper cylinder is repelled by the positively charged rod. And when you bring a negatively rubbed rod, next to the cylinder it will be attracted towards the rod. This means that the paper cylinder has acquired a positive charge as on the glass rod due to conduction.
-- Looking at the dots casually, they look green because they absorb all other
colors of light, and only green light is left to proceed to your eyes. (In order for
this to work, there has to be some green in the light shining on the dots.
Daylight and most light bulbs work fine.)
-- The filter looks red because it absorbs all other colors of light, and only
the red light is left to pass through the filter and come out on the other side.
-- When the green light from the dots hits the red filter, it's absorbed in the
filter, and there's no light left to come out on the other side.
If you're looking through the filter at the dots, they look <em>black</em>.
(F)(M)=A
Force times Mass equals Acceleration.
The answer is TRUE.
If the mass increases the number on the left side of the equation increases, thus increasing the right side as well.
