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
natka813 [3]
3 years ago
10

Which of the following is a complex machine? 1) piano 2) bottle opener 3) shoehorn 4) doorknob

Physics
2 answers:
erastovalidia [21]3 years ago
7 0
I would say 1) piano because the doorknob is only the wheel and axle. 
xeze [42]3 years ago
5 0
1. piano. that is the answer is my mind
You might be interested in
Explain nuclear reactions, nuclear fission and nuclear fusion.
SVETLANKA909090 [29]

Answer:

Nuclear reaction is a reaction in which nucleus of the atom undergoes a change.

Nuclear fusion is a process which involves the conversion of two small nuclei to form a heavy nuclei along with release of energy.

Example : 4_1^1\textrm{H}\rightarrow _2^4\textrm{He}+2_{+1}^0\textrm{e}+\text{energy}

Nuclear fission is a process which involves the conversion of a heavier nuclei into two or more small and stable nuclei along with the release of energy.

Example: _{92}^{235}\textrm{U}+_0^1\textrm{n}\rightarrow _{56}^{143}Ba+_{36}^{90}Kr+3_0^1\textrm{n}

8 0
3 years ago
If you run the simulation a few times, you should see that for this particular pair of block and disc the block's position has t
user100 [1]

Explanation:

C) is incorrect.  The mass is equivalent to the moment of inertia in an angular formula.

The others appear all correct.

T * theta = F * r * theta = F * (r theta) = fx = work

This is the only one that needed explanation.  The others should be obvious.

7 0
3 years ago
A golfer strikes a 0.059-kg golf ball with a force of 290 N. If the ball moves with a velocity of 69 m/s,
Ymorist [56]

Answer:

0.014s

Explanation:

Given parameters:

mass of golf ball  = 0.059kg

force applied  = 290N

velocity = 69m/s

initial velocity  = 0m/s

Unknown:

Time of contact  = ?

Solution;

We know that momentum is the quantity of motion of body possess;

  Momentum  = mass x velocity

  Momentum  = 0.059 x 69  = 4.1kgm/s

Also; impulse is the effect of the force acting on a body;

  impulse  = force x time  = momentum

  So;

            Force x time  = momentum

                  Time  = \frac{momentum}{force }    = \frac{4.1}{290}    = 0.014s

 

 

4 0
3 years ago
Why does an iceberg have more HEAT than a cup of coffee?
Drupady [299]

Answer:

The hot coffee has a higher temperature, but not a greater internal energy. Although the iceberg has less internal energy per mass, its enormously greater mass gives it a greater total energy than that in the small cup of coffee.

Explanation:

3 0
3 years ago
Read 2 more answers
Which term best describes the process that occurs when light passes through a lens? A. reflection B. refraction C. resonance D.
Elza [17]
A. Refraction, meaning the same thing...it just passes through. Reflection is when light, heat, or sound bounces off a surface, kind of like an echo. Resonance is sound reverberating, or vibrating. And polarization is the action of not allowing the vibrations of a transverse wave. Hoped this helps you :) 

Short answer: Refraction
3 0
3 years ago
Read 2 more answers
Other questions:
  • A rock (mass 45 kg) falls into a ravine. What is the force of air resistance when it has reached terminal velocity.?
    6·1 answer
  • If there is an object in top of another object, why does the upper object exert a downward normal force?​
    12·1 answer
  • A child and sled with a combined mass of 50.2 kg slide down a frictionless hill that is 8.38 m high. If the sled starts from res
    9·1 answer
  • within ____minutes after a drink is consumed all of the alcoholic content has probably been absorbed into your body
    7·1 answer
  • Find the intensity of electromagnetic radiation at the surface of the sun (radius r=R=6.96×105kmr=R=6.96×105km). Ignore any scat
    13·1 answer
  • I need this quick!!!! In middle of a quiz
    9·1 answer
  • What best describes why kepler’s observation of planetary motion is a law instead of a theory
    11·1 answer
  • Will chlorine water react with potassium fluoride solution? If not, why?
    14·2 answers
  • Plz answer the question in the image below
    13·1 answer
  • The acceleration of gravity is approximately 10 m/s2. What would the force of gravity be if the mass of an object is 4.5 kg?
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!