Answer:
During convection, hot material expands & rises then moves to the side and cools & sinks. this circular pattern is called a convection current.
Explanation:
Convection is one of the three methods of transfer of heat. It occurs only in fluids (liquids or gases).
Convection occurs when there is a source of heat that heats a fluid, such as in a boiling pot of water. The water which is on the bottom of the pot becomes warmer before than the water at the top (because it is closer to the flame), and so it becomes less dense: for this reason, it expands and it becomes rising. On the contrary, the water on top is colder, so it is more dense and starts sinking, replacing the warmer water. As the new part of water gets warmer, it starts rising, and so the process is continuously repeated. This circular current is called convection current.
Answer:
The force of the car engine.
Explanation:
The work- energy theorem states that the work done on an object is equal to the change in its kinetic energy. Its expression is given by :
Also, W = F.d
Where
F is the force applied by the engine of car
d is the displacement
m is the mass of an object
u is the initial speed
v is the final speed
So, the force of the car engine increased the car’s kinetic energy. Hence, this is the required solution.
The data for the first part of the experiment support the first hypothesis. As the force applied to the cart increased, the acceleration of the cart increased. Since the increase in the applied force caused the increase in the cart's acceleration, force and acceleration are directly proportional to each other, which is in accordance with Newton's second law.
Answer:
Explanation:
As we know Newton's II law
= Rate of change in momentum
so we will have
now we will have
so here we can say that change in momentum of the object is the product of force and interval of time for which the force is acting on it.
so we will have
Answer:
Energy gained by the second particle = 12Uo
Explanation:
Given Data;
Resistant force = 12F
Initial kinetic energy = Uo
Calculating the kinetic energy gained, we have;
u = f *r
where f= resistant force = 20F
r = initial kinetic energy = Uo
Therefore,
U = 12 * uo
= 12 Uo
Therefore, energy gained by the second particle = 12Uo
