Complete question:
(b) How much energy must be supplied to boil 2kg of water? providing that the specific latent heat of vaporization of water is 330 kJ/kg. The initial temperature of the water is 20 ⁰C
Answer:
The energy that must be supplied to boil the given mass of the water is 672,000 J
Explanation:
Given;
mass of water, m = 2 kg
heat of vaporization of water, L = 330 kJ/kg
initial temperature of water, t = 20 ⁰C
specific heat capacity of water, c = 4200 J/kg⁰C
Assuming no mass of the water is lost through vaporization, the energy needed to boil the given water is calculated as;
Q = mc(100 - 20)
Q = 2 x 4200 x (80)
Q = 672,000 J
Q = 672,000 J
Q = 672,000 J
Therefore, the energy that must be supplied to boil the given mass of the water is 672,000 J
(b) During one day, 250 kg of water is pumped through
the solar panel. The température of this
water rises from 16°C to 38°C.
The water absorbs 25% of the energy incident on the solar panel. The
specific heat capacity
of water is 4200J/(kg °C).
Calculate the energy incident on the solar panel during that day.
Please explain how to find the incident energy
Answer: The energy incident on the solar panel during that day is [tex]9.24 \times 10^{7} J[/tex].
Explanation:
Given: Mass = 250 kg
Initial temperature = [tex]16^{o}C[/tex]
Final temperature = [tex]38^{o}C[/tex]
Specific heat capacity = 4200 [tex]J/kg^{o}C[/tex]
Formula used to calculate the energy is as follows.
[tex]q = m \times C \times (T_{2} - T_{1})[/tex]
where,
q = heat energy
m = mass of substance
C = specific heat capacity
[tex]T_{1}[/tex] = initial temperature
[tex]T_{2}[/tex] = final temperature
Substitute the values into above formula as follows.
[tex]q = 250 kg \times 4200 J/kg^{o}C \times (38 - 16)^{o}C\\= 250 kg \times 4200 J/kg^{o}C \times 22^{o}C[/tex]
As it is given that water absorbs 25% of the energy incident on the solar panel. Hence, energy incident on the solar panel can be calculated as follows.
[tex]\frac{25}{100} \times q = 250 kg \times 4200 J/kg^{o}C \times 22^{o}C\\q = 9.24 \times 10^{7} J[/tex]
Thus, we can conclude that the energy incident on the solar panel during that day is [tex]9.24 \times 10^{7} J[/tex].
a man runs 1200m on a straight line in 4 min . find his velocity.
Answer:
5m/sec^2
Explanation:
Distance=1200m
Time=4 min
1=60sec
4=4 x 60
=240sec
Velocity=Distance/Time
Velocity=1200/240
Velocity=5m/sec^2
Mark me as brainliest
How is an ammeter connected in a circuit to measure current flowing through it?
Answer:
It is connected in series with the circuit
Explanation:
This is because to measure the current in the circuit, the current in the circuit has to flow through the ammeter. As such, the ammeter must be connected in series with the circuit so as to measure the current flowing through the circuit.
So, to measure the current flowing through a circuit with an ammeter, the ammeter must be connected in series with the circuit.
The energy of an electromagnetic wave changes proportionally to which
other property?
O A Speed
O B. Shift
O c. Wavelength
O D. Frequency
Answer:
D. Frequency
Explanation:
The energy of an electromagnetic wave is proportional to frequency, mathematically it is expressed as;
E ∝ f
E = hf
where;
h is Planck's constant = 6.626 x 10⁻³⁴ Js
The equation above can also be expanded to;
[tex]E = hf = h \frac{c}{\lambda}[/tex]
where;
c is speed of light = 3 x 10⁸ m/s
λ is the wavelength of the electromagnetic wave
Since the speed of light is constant, we can conclude that the energy of the electromagnetic wave is directly proportional to its frequency and inversely proportional to its wavelength.
Therefore, the correct option for direct proportionality is FREQUENCY
Multiplying a vector with another vector results in what type of answer.
A) a direction
B) a vector
C) either a vector or a scalar
D) a scalar
multiplication of two vectors yields a vector oroduy
As Courtney switches on the TV set to watch her favorite cartoon, the electron beam in the TV tube is steered across the screen by the field between two charged plates. If the electron experiences a force of 3.0 * 10^6 N, how large is the field between the deflection plates?
Answer:
Explanation:
Force= (q1q2)/(4/\Ęr2)
3×10^6= (1.602×10^-19)^2/(r^2)
r^2=(2.27×10^-33)/(3×10^6)
r^2=8.55×10^-45
r= 9.25×10^-23
help please!!
From the following images shown, classify the interactions that occur and say between which bodies, according to the following criteria:
a) Contact forces
b) Non-contact forces
Answer:
B= 4 A=5
Explanation:
The velocity of sound in a medium increases with increasing
a. distance
b. amplitude
c. temperature
d. time
c- temperature
The speed of sound increases with increasing temperature .
