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
NISA [10]
2 years ago
12

4.

Physics
1 answer:
galina1969 [7]2 years ago
8 0

Answer:

72%

Calculating Efficiency:

The amount of work obtained from a machine is always less than the amount of work put into it. Thisis because some of the work is lost due to friction. The efficiency of a machine can be calculated usingthe following formula:Percent Efficiency = (work output-Machine / work input-You) x 100%

You might be interested in
4. A substance has a density of 0.79 g/cm'. It is soluble in water. List all the possibilities of what it might be How could you
Natasha_Volkova [10]

Answer:

See explanation

Explanation:

Given that the density of the unknown substance is 0.79 g/cm3 and is soluble in water, the possible substances it could be are;

i) t-butanol

ii) ethanol

iii) 2-propanol

iv) acetone

However, the actual identity of the unknown substance can be obtained by carrying out a boiling point test. The four substances listed above have different boiling points. Hence the boiling point of the unknown substance ultimately discloses its identity.

5 0
3 years ago
If a car accelerates uniformly from rest to 15 meters
Talja [164]

Answer:

1.125m/s^2

Explanation:

Since acceleration is defined as the rate of change in velocity with respect to time. Mathematically

v^2= u^2+2as

Where a,v,u and s are the acceleration, final velocity, initial velocity and distance respectively.

a = ?

u = 0m/s

v = 15m/s

s = 100m

Substituting the values into the formula above

v^2= u^2+2as

15^2=0^2+2×a×100

225= 0+200a

225= 200a

Divide both sides by 200

225/200 = 200a/200

a= 1.125m/s^2

Hence the acceleration of the car is 1.125m/s^2.

Note that the car accelerated uniformly from rest, that was why the initial velocity was 0m/s

8 0
3 years ago
Read 2 more answers
John pushes a box with a constant force as shown in the graph below.
andrew11 [14]
From the graph, it can be seen that the constant force that John exerted in order to move the object is 14N. Work is calculated by multiplying the force with the distance to which the object moves in parallel with the direction of the force. 
                                      Work = Force x displacement
                                      Work = (14 N) x (8 m)
                                        Work = 112 J
The closest value is 110J. Thus, the answer to this item is the second choice. 
4 0
3 years ago
When looking at a graph what are the first 3 things you should do?
Valentin [98]

Answer: Look where the points are.

Explanation:

4 0
2 years ago
Read 2 more answers
Determine the amount of potential energy of a 5.0Kg book that is moved to three different shelves on a bookcase. The height of e
rjkz [21]
Formula to find gravitational potential energy:
mgh
m: mass
g: gravitational acceleration
h: height (relative to reference level)

so the P.E. at 1.0.m is (5x9.8x1)= 49J
P.E. at 1.5m is (5x9.8x1.5) =73.5J
P.E. at 2.0m is (5x9.8x2)=98J
8 0
3 years ago
Other questions:
  • A girl sitting on a merry-go-round moves counterclockwise through an arc length of 3.15 m.
    8·1 answer
  • What happens during the apparent retrograde motion of a planet?
    14·1 answer
  • PLEASE HELP!!!
    12·2 answers
  • If it requires 4.0 J of work to stretch a particular spring by 2.0 cm from its equilibrium length, how much more work will be re
    10·1 answer
  • A small wooden block with mass m1 is suspended from the lower end of a light cord that is l long. The block is initially at rest
    9·1 answer
  • What is the CGS unit of current?
    10·2 answers
  • 3.A carnival ride has a radius of 5.00 m and exerts an applied force of 987 N on an 80 kg rider.
    7·1 answer
  • 9.00 V is applied to a wire with a resistance of 52.0 ohm. At what distance from the wire is the magnetic field 2.22x 10^-8 T?
    15·1 answer
  • How does Physics help you as a student?
    15·2 answers
  • A bungee jumper who is about to jump has her energy stored entirely as
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!