A:True because Lithium is the lighest solid and metal and the third lightest element.
Answer:
v=115 m/s
or
v=414 km/h
Explanation:
Given data

To find
Terminal velocity (in meters per second and kilometers per hour)
Solution
At terminal speed the weight equal the drag force

For speed in km/h(kilometers per hour)
To convert m/s to km/h you need to multiply the speed value by 3.6
Well, the tension in the thread will probably quadruple, but the hanging body will continue to just hang there.
The question gives us no evidence that it is doing any oscillating, and there's no reason for it to start just because it suddenly got heavier.
Answer: The correct option is Option b.
Explanation:
Power is defined as the rate of work done by an object.
Mathematically,
.....(1)
And work done is the product of force exerted on the object times the displacement covered by that object.
Mathematically,

Putting this value in above equation, we get:

where,
P = power = ?W
F = Force exerted = 10N
s = Displacement = 400cm = 4m (Conversion factor: 1m = 100 cm)
t = Time taken = 8s
Putting values in above equation, we get

Hence, the correct option is Option b.