When you heat a certain substance with a difference of temperature

the heat (energy) you must give to it is

where

is the specific heat of that substance (given in J/(g*Celsius))
In this case

Observation: the specific heat of a substance is given in J/(g*Celsius) or J/(g*Kelvin) because on the temperature scale a
difference of 1 degree Celsius = 1 degree Kelvin
<span>Given:
3,500 kilometers
Find:</span>
Years for two continents to collide = ?
<span>Solution:
We know that </span>typical motions of one plate relative to another
are 1 centimeter per year.
So first, we convert 3,500 km to cm.<span>
</span><span>
</span>
The solution would be like this for this specific problem:
1 km = 100,000 cm
3,500 km x 100,000 = 350,000,000 cm
Since we know that 1 cm = 1 year, then that means
350,000,000 cm is equivalent to 350,000,000 years.
Therefore, it would take 350 million years for two continents
that are 3500 kilometers apart to collide.
<span>
To add, </span>a phenomenon of the plate tectonics of Earth that occurs at
convergent boundaries is called the continental collision.
Because upward buoyant force is slightly higher than gravitation force for this particular object
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.