<span>We know the change of thermal energy is proportional to the specific heat of the matter, its mass and the change of temperatures, according the following formula:
Q = C*m*(Tf-Ti)
where:
Q is the heat added or removed (in joules, J)
C is the specific heat of the matter, in our case air 1,000 J/(Kg*C)
m is the mass, in our case 50 kg of air
Tf is final temperature
Ti is initial temperature
then:
Q = 1000 * 50 * (30-20) = 500,000 Joules
That means that 500,000 joules need to be added to increase temperature of the room 10 ÂşC (from 20 to 30 ÂşC)</span>
Answer:
The correct answers to the question are
1. Environmental variable c,
2. Input variable a,
3. Output variable b,
4. Input variable a,
5. Input variable a,
6. Input variable a
Explanation:
1. Outside temperature.
This is is an environmental variable regarding where the observation is taking place
2. Duration that the soup was heated before being put in the bowl.
This can be controlled so it is an input variable
3. Temperature of the soup in a student's bowl.
This depends on the initial temperature the soup was heated to so it is an output variable
4. Temperature level to which the soup is warmed up.
Input variable as it can be controlled o varied
5. Insulation of the bowl used for storing the soup.
This is an input variable as the type of bowl can be selected
6. Duration that the soup bowl is open when the server inserts the ladle to serve a student.
server or the operator of the cafeteria
Answer:
The height of the ball, h = 81.63 m
The velocity of the ball at the highest point is zero
Explanation:
Given data,
The mass of the ball, m = 1 kg
The initial velocity of the ball, u = 40 m/s
Using the conservation of energy, the total mechanical energy of the ball initially at u = 40 m/s
E = P.E + K.E
E = 0 + ½ mv²
= ½ x 1 x 40²
= 800 J
The maximum height the ball reaches with the energy E = 20 J
The K.E of the ball is zero at the maximum height
E = mgh
h = E / mg
= 800 / (1 x 9.8)
= 81.63 m
The height of the ball, h = 81.63 m
The velocity of the ball at the highest point is zero.
<span>Well, I just took this unit. There are two main kinds of cells, which are made up of smaller organelles: Nucleus, Vacuoles etc. The two main types are Plant and animal. Only Plant cells have walls.</span><span />
Answer:
acceleration m/s²
Explanation:
The units on the left side of the equation are units of length. The units on the right side of the equation must be units of length also. Acceleration times time squared gives length.