Explanation:
- A thermometer does measure the temperature of a body and not the heat. It is known that temperature is a measure of average kinetic energy.
Therefore, the statement a thermometer measures the average kinetic energy of a substance is correct.
- Heat is a form of energy as it can make a colder substance become hot and it moves from one place to another. Thus, the statement heat is a form of energy is correct.
- Also, heat flows from hotter substance to colder substance. Hence, the statement heat flows from a colder substance to a hotter substance is correct.
- Convection is a property of fluids or gases which makes less denser (hot) material to rise and more denser (colder) material to sink.
Therefore, the statement convection occurs only in liquids and gases is correct.
- All substances radiate heat is an incorrect statement. For example, a thermos bottle does not radiate heat.
- Temperature of our body is about 98.4 degree celsius and hence we can conclude that the statement our body temperature is always equal to the temperature around us is incorrect.
You mean like a box sitting on a table.
One force is the force of gravity, pulling downward on the box.
Now, you know that the forces acting on the box must be balanced, because
if they're not, then the box would be accelerating. But it's just sitting there, so
there must be some other force, just exactly the right strength and direction to
exactly cancel the force of gravity on the box, so that the net force on it is zero.
The other force is the force of the table pushing upward on the box. It's called
the "normal force".
Answer:
The force of the ball on the bat is same as the force of the bat on the ball.
Explanation:
A bat hits the ball and the ball moves to the out filed.
According to the Newton's third law, for every action there is an equal and opposite reaction.
The action and the reaction forces acts on the two different bodies but the magnitude of the force is same.
As the ball is hitted by the bat, the bat exerts the force on the ball and the same force is exerted on the bat by the ball according to the Newton's third law.
So, the force of the ball on the bat is same as the force of the bat on the ball but the direction of force is opposite.
Answer:
The velocity of charge is 1.1×10⁴
Option(D)
Explanation:
F = q(v×B)
3.5×10-²= (8.4×10-⁴)*(v)*(6.7×10-³)*sin35
v = (3.5)/(8.4×6.7×0.57) × 10⁵
v = 3.5/32.08 × 10⁵
v = 0.109 × 10⁵
v ≈ 1.1 × 10⁴ m/s
This would be a cold front that forms when a warm air mass meets the area of a cooler air mass, although it should be noted that this doesn't always feel "cold".
