Assuming that there is no heat loss, and the cup is perfectly insulated, all of the energy lost by the lead will be absorbed by the water.
The heat absorbed is given by:
Energy = mass * specific heat capacity * change in temperature
The specific heat capacity of water is 4.18 joules per gram.
In order to compute the mass, we will use the fact that the density of water is one gram per milliliter. Therefore, the mass of water is 50 grams.
Now,
Q = 50 * 4.18 * (20 - 18)
Q = 418 J
418 Joules of energy were released by the lead.
The Cell Body is the part of the neuron that decides whether the message will travel
Pressure applied on a system is calculated by dividing the force by the area perpendicular to the direction of the force. It is expressed as:
P = F/A = 1.5 N / 0.5 m^2 = 3 N/m^2
Therefore, the correct answer from the choices is the last option. Hope this answers the question. Have a nice day.
Answer:
A. 1254.4 J
B. 1254.4 J
C. 43904 calories
Explanation:
Parameters given:
Mass of barbell, m = 160 kg
Length of arm, d = 0.8
A. Work done by weight lifter in lifting the barbell is:
W = F * d
Where F is force
F = m * g
=> W = m * g * d
W = 160 * 9.8 *0.8
W = 1254.4 J
B. Potential energy is given as:
PE = m * g * h
Where h is height (in this case, D)
=> PE = m * g * d
PE = 160 * 9.8 * 0.8
PE = 1254.4 J
C. The number of calories the weight lifter uses after lifting the barbell 35 times is equal to 35 times the potential energy, since a calorie is the measure of the amount of potential energy a piece of food contains:
35 * 1254.4 = 43904 calories.
