1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Ipatiy [6.2K]
3 years ago
15

Number 29 plz help physics

Physics
1 answer:
svetoff [14.1K]3 years ago
8 0

Answer:

a. E = 900000 J = 900 KJ

b. ΔT = 8.18 °C

c. Cost = $ 7.2  

Explanation:

a.

The energy can be given by:

E = Pt

where,

E = Energy = ?

P = Power = 500 W

t = time = (0.5 h)(3600 s/1 h) = 1800 s

Therefore,

E = (500\ W)(1800\ s)

<u>E = 900000 J = 900 KJ</u>

b.

The change in temperature of room air is given by the following formula:

0.5E = mC\Delta T\\   (since 50% of energy is used to heat air)

where,

m = mass of air = 50 kg

C = specific heat of air = 1.1 KJ/kg.°C

ΔT = Change in temperature of air = ?

Therefore,

(0.5)(900\ KJ) = (50\ kg)(1.1\ KJ/Kg.^oC)\Delta T

<u>ΔT = 8.18 °C</u>

c.

First, we will calculate the total energy consumed:

E = (0.5\ KW)(6\ h/d)(30\ d)\\E = 90\ KWh

Now, for the cost:

Cost = (Unit\ Cost)(Energy)\\Cost = (\$ 0.08\KWh)(90\ KWh)

<u>Cost = $ 7.2</u>

You might be interested in
A solid yellow line on your side of the center stripe means pass with care.<br> A. True<br> B. False
oee [108]

Answer:

B

Explanation:

a straight yellow is a no pass zone

7 0
3 years ago
In the southern hemisphere, the longest day of the year happens during _____.
Luden [163]
I think it is June. June is the longest day/
8 0
3 years ago
Read 2 more answers
A. The potential energy stored in the compressed spring of a dart gun, with a spring constant of 62.00 N/m, is 0.940 J. Find by
valina [46]

a. The spring is compressed  by  0.174 m.

b.  The vertical distance the dart travels from its position when the spring is compressed to its highest position is 9.6 m.

c. The horizontal velocity of the dart at that time is  13.74 m/s.

d. The horizontal distance from the equilibrium position at which the dart hits the ground is 19.236 m.

<h3>What is potential energy?</h3>

The energy by virtue of its position is called the potential energy.

a. Given is the potential energy stored in the compressed spring of a dart gun, with a spring constant of 62.00 N/m, is 0.940 J.

PE  of spring = 1/2 kx²

Put the values, we get

P.E = 0.940 = 1/2 x 62 x²

x = 0.174 m

Thus, the spring is compressed by 0.174 m.

b. Given is a 0.010 kg dart is fired straight up.

The vertical height is find out by

0.940 J = (0.010 kg) (9.8 m/s²) h

h = 9.6 m

Thus, the vertical distance the dart travels from its position is 9.6 m

c. From the conservation of energy principle, total mechanical energy is conserved.

1/2 mv² =mgh

v = √2gh

Plug the values, we get

v = √2 x 9.8x 9.6

v = 13.74 m/s

Thus, the horizontal velocity is  13.74 m/s.

d.  Time that dart spends in air, t = √2h/g

t = √(2x9.6)/9.81

t = 1.4 s

The horizontal distance from the equilibrium position at which the dart hits the ground.

Horizontal distance = (Velocity on x direction) x time

Horizontal distance = 13.74 m/s x 1.4s

Horizontal distance = 19.236 m

Thus, the horizontal distance is 19.236 m.

Learn more about potential energy.

brainly.com/question/24284560

#SPJ1

7 0
2 years ago
The metric unit to measure work which equals one newton meter<br> is called?
Solnce55 [7]
The metric unit to measure work which equals one newton meter is called One Joule.
8 0
3 years ago
A small circular coil of 5 turns of wire lies in a uniform magnetic field of 0.8 T, so that the normal to the plane of the coil
Travka [436]

Complete question:

A small circular coil of 5 turns of wire lies in a uniform magnetic field of 0.8 T, so that the normal to the plane of the coil makes an angle of 100◦ with the direction of B~ . The radius of the coil is 4 cm, and it carries a current of 1 A.

What is magnitude of the magnetic moment of the coil? Answer in units of A · m2.

Answer:

The magnetic moment of the coil is 0.0252 A.m²

Explanation:

Given;

radius of the coil, r = 4 cm = 0.04 m

number of turns of the coil, N = 5 turns

magnetic field strength B = 0.8 T

current in the coil, I = 1 A

Area of the coil, A = πr² = π(0.04)² = 0.00503 m²

magnetic moment of the coil, μ = NIA

where;

N is the number of turns

I is the current in the coil

A is the area of the coil

magnetic moment of the coil, μ = 5 x 1 x 0.00503 = 0.0252 A.m²

Therefore, the magnetic moment of the coil is 0.0252 A.m²

8 0
3 years ago
Other questions:
  • An experiment is conducted in which red light is diffracted through a single slit. part a listed below are alterations made, one
    8·2 answers
  • Jason applies a force of 4.00 newtons to a sled at an angle 62.0 degrees from the ground. What is the component of force effecti
    12·1 answer
  • When Lisa placed a balloon to her ear, she was able to hear what her sister was whispering from the other side of the room. When
    6·2 answers
  • A bicycle pedal is pushed straight downwards by a foot with a 16 Newton force. The shaft of the pedal is 20 cm long. If the shaf
    6·1 answer
  • Explain why a magnet from your refrigerator could not be used to life something as heavy as a car ?
    14·1 answer
  • A person is riding on a Ferris wheel of radius R. He starts at the lowest point of the wheel. When the wheel makes one complete
    6·1 answer
  • Two stones, one of mass m and the other of mass 2m, are thrown directly upward with the same velocity at the same time from grou
    9·1 answer
  • A kind of tempory magnet​
    7·2 answers
  • If a body is accelerating m change the velocity of 2 metre per second square when it was acted by five hundred Newton of force t
    11·2 answers
  • What is the unit of velocity ratio and why​
    10·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!