The answer is "the specific heat of the substance".
In fact, specific heat is a property of every substance that tells how much heat is needed to raise the temperature of a certain amount of that substance by 1 degree.
Using formula:
where
is the increase in temperature of the substance, Q is the amount of heat absorbed by the substance, m is its mass and Cs is the specific heat of that substance.
In the problem, the mass of the water and of the wood is the same (1 kg), and they absorb the same amount of heat, Q. But the change in temperature
of the wood is larger than the water, and the explanation for this is that the specific heat Cs of the wood is smaller than the specific heat of water.
In fact, looking at tables we have that specific heat for water is 1 J/(g C), while for wood is approximately 0.4 J/(g C).
Answer:
A
Explanation:
Forces are vector quantities because they have both magnitude and direction.
1) We can solve this part of the problem by using the law of conservation of energy. In fact, the initial energy of the ball is just kinetic energy:
where m is the mass of the ball and v is the initial speed of the ball. At its maximum height, the speed of the ball is zero, so its energy is just gravitational potential energy:
where g is the gravitational acceleration and h is the height above the ground.
Since the total energy must be conserved, we have
which means
If we use h=45 m, we find the minimum speed v such that the ball reaches an altitude of 45 m above the ground:
2) The motion of the ball is an accelerated motion, and the relationship between the distance covered by the ball and the time t is given by
where t is the time the ball takes to reach the altitude h=45 m. Rearranging the equation, we find
Answer:
V = 192 kV
Explanation:
Given that,
Charge,
Distance, r = 0.3 m
We need to find the electric potential at a distance of 0.3 m from a point charge. The formula for electric potential is given by :
So, the required electric potential is 192 kV.