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
erastovalidia [21]
3 years ago
12

A man weighs himself twice in an elevator. When the elevator is at rest, he weighs 824 N; when the elevator starts moving upward

, he weighs 932 N. Most nearly how fast is the elevator accelerating, assuming constant acceleration?
a. 0.64 m/s
b. 1.1 m/s^2
c. 1.3 m/s
d. 9.8 m/s^2
Physics
1 answer:
kifflom [539]3 years ago
3 0

Answer: c. 1.3 m/s^2

Explanation:

When he is at rest, is weight can be calculated as:

W = g*m

where:

m = mass of the man

g = gravitational acceleration = 9.8m/s^2

We know that at rest his weight is W = 824N, then we have:

824N = m*9.8m/s^2

824N/(9.8m/s^2) = m = 84.1 kg

Now, when the elevators moves up with an acceleration a, the acceleration that the man inside fells down is g + a.

Then the new weight is calculated as:

W = m*(g + a)

and we know that in this case:

W = 932N

g = 9.8m/s^2

m = 84.1 kg

Then we can find the value of a if we solve:

932N = 84.1kg*(9.8m/s^2 + a)

932N/84.1kg = 11.1 m/s^2 = 9.8m/s^2 + a

11.1 m/s^2 - 9.8m/s^2 = a = 1.3 m/s^2

The correct option is C

You might be interested in
As you know, the oceans cover most of the earth, and contain a huge amount of resources. Protecting these resources is one reaso
matrenka [14]
A is the answer your looking for
8 0
3 years ago
Read 2 more answers
Has anyone done the science project: modeling waves/properties of light?
igor_vitrenko [27]
<h2>MARK BRAINLIEST</h2>

For this assignment, you will develop several models that show how light waves and mechanical waves are reflected, absorbed, or transmitted through various materials. For each model, you will write a brief description of the interaction between the wave and the material. You will also compose two <u><em>typewritten</em></u> paragraphs. The first will compare and contrast light waves interacting with different materials. The second will explain why materials with certain properties are well suited for particular functions.

<h2><u>Background Information</u></h2>

A wave is any disturbance that carries energy from one place to another. There are two different types of waves: mechanical and electromagnetic. A mechanical wave carries energy through matter. Energy is transferred through vibrating particles of matter. Examples of mechanical waves include ocean waves, sound waves, and seismic waves. Like a mechanical wave, an electromagnetic wave can also carry energy through matter. However, unlike a mechanical wave, an electromagnetic wave does not need particles of matter to carry energy. Examples of electromagnetic waves include microwaves, visible light, X-rays, and radiation from the Sun.

7 0
3 years ago
Read 2 more answers
How high was a brick dropped from if if falls in 2.5 seconds?
jenyasd209 [6]
Using the kinematic equation d =  V_0 * t  + 1/2 * a * t^2, where d is height you can rewrite this to be d = 1/2*g*t^2 or 4.9t^2
g = a because this is a free fall 
d = 1/2 * 9.81m/s^2 * 2.5^2
d = 30.65625m
d = 30.7m
7 0
2 years ago
A high-jumper clears the bar and has a downward velocity of - 5.00 m/s just before landing on an air mattress and bouncing up at
Jobisdone [24]

-- As she lands on the air mattress, her momentum is (m v)

Momentum = (60 kg) (5 m/s down) = 300 kg-m/s down

-- As she leaves it after the bounce,

Momentum = (60 kg) (1 m/s up) = 60 kg-m/s up

-- The impulse (change in momentum) is

Change = (60 kg-m/s up) - (300 kg-m/s down)

Magnitude of the change = <em>360 km-m/s </em>

The direction of the change is <em>up /\ </em>.

8 0
3 years ago
A 2.0-kg mass is projected from the edge of the top of a 20-m tall building with a velocity of 24 m/s at some unknown angle abov
Digiron [165]

Ox:vₓ=v₀

x=v₀t

Oy:y=h-gt²/2

|vy|=gt

tgα=|vy|/vₓ=gt/v₀=>t=v₀tgα/g

y=0=>h=gt²/2=v₀²tg²α/2g=>tgα=√(2gh/v₀²)=√(2*10*20/24²)=√(400/576)=0.83=>α=tg⁻¹0.83=39°

cosα=vₓ/v=v₀/v=>v=v₀/cosα=24/cos39°=24/0,77=31.16 m/s

Ec=mv²/2=2*31.16²/2=971.47 J=>Ec≈0.97 kJ

3 0
2 years ago
Other questions:
  • A car is traveling in a race. The car went from the initial velocity of 35 m/s to the final velocity of 65 m/s in 5 seconds. Wha
    11·1 answer
  • While discussing the effects of loose wheel bearings: Technician A says that vibration may occur while driving. Technician B say
    12·1 answer
  • The velocity of waves in a ripple tank is 10 centimeters per second, and standing waves are produced with nodes spaced 3.0 centi
    6·2 answers
  • What is the purpose of the lab, the importance of the topic, and the question you are trying to answer?
    6·2 answers
  • How does the ocean play an important role in climate and climate change? Keep answer related to the specific heat capacity of wa
    15·1 answer
  • 2 examples of where ground water comes from
    5·2 answers
  • Qualitative observation requires numerous data to discribe research A .true B. False
    9·1 answer
  • Suggest two ways in which the boy could balance the beam?
    12·2 answers
  • Can atoms go bad?, not in the reversible way like ionization and isotopes but really malfunction our die.​
    14·1 answer
  • A bromine atom has an atomic number of 35 and an atomic mass of 80. What is the structure of this atom?
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!