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
morpeh [17]
3 years ago
9

a 45kg box of books is lifted o a bookself 1.75 m above the floor. how much work was done to lift the books?

Physics
1 answer:
jekas [21]3 years ago
7 0

Answer:

770 J

Explanation:

W = PE

W = mgh

W = (45 kg) (9.8 m/s²) (1.75 m)

W = 770 J

You might be interested in
A student drops a rock from a bridge to the water 12m below. How many seconds does it take the rock to hit the water?
ANEK [815]
R = \frac{g t^{2} }{2}
r - displacement or height
t - time taken
g = 10 m/s-2
t = square root from 2r/g = \sqrt{ \frac{2 x 12}{10} } = 1.5 seconds
7 0
3 years ago
1. The 10-min unithydrograph for a 2.25 km2 urban catchment is given by:(a) estimate the run off hydrograph for a 10-min rainfal
vivado [14]

Answer:

A ) Find the direct runoff depth; d =V A 22,698 _ 2.25x106 =0.01m =1cm The above result shows that the given hydrograph qualifies as a unit hydrograph. .

Explanation:

Brainlyist

5 0
3 years ago
Light with a wavelength of about 490 nm is made to pass through a diffraction grating. the angle formed between the path of the
polet [3.4K]

The number of lines per mm in the diffraction grating is 326.

<h3>What is diffraction grating?</h3>

A diffraction grating is a type of optical instrument obtained with a continuous pattern. The pattern of the diffracted light by a grating depends on the structure and number of elements present.

The given data in the problem is

\rm \theta is the angle formed between the path of the incident light and the diffracted light = 9. 2°

λ is the wavelength of the light=490nm=4.9

N is the number of lines per mm in the diffraction grating=?

n is ordered = 1

The formula for the diffraction grating is;

n \lambda = d sin\theta \\\\ d = \frac{n \lambda}{sin \theta } \\\\  d = \frac{1 \times 4.90 \times 10^{-7}}{sin 9.2^0 } \\\\ d=3.06 \times 10^{-6} \\\\ d=3.06 \times 10^{-3} \ mm

The number of lines per mm is found as;

\rm N= \frac{1}{d} \\\\ N= \frac{1}{3.06 \TIMES 10^{-3}} \\\\ N=326.8 /mm

Hence the number of lines per mm in the diffraction grating is 326.

To learn more about diffraction grating refer to the link;

brainly.com/question/1812927

5 0
3 years ago
A 82-kg fisherman in a 112-kg boat throws a package of mass m = 15 kg horizontally toward the right with a speed of vi = 4.8 m/s
abruzzese [7]

Answer:

0.37 m/s to the left

Explanation:

Momentum is conserved.  Initial momentum = final momentum.

m₁ u₁ + m₂ u₂ = m₁ v₁ + m₂ v₂

Initially, both the fisherman/boat and the package are at rest.

0 = m₁ v₁ + m₂ v₂

Plugging in values and solving:

0 = (82 kg + 112 kg) v + (15 kg) (4.8 m/s)

v = -0.37 m/s

The boat's velocity is 0.37 m/s to the left.

8 0
3 years ago
Diffrence between:- movable pulley and fixed pully​
kotykmax [81]

Answer:

fixed pulley: A pulley system in which the pulley is attached to a fixed point and the rope is attached to the object. ... movable pulley: A pulley system in which the pulley is attached to the object; one end of the rope is attached to a fixed point and the other end of the rope is free.

Explanation:

8 0
3 years ago
Other questions:
  • When triggers nuclear fusion in stars
    5·1 answer
  • What are the basic primitive solids?
    8·1 answer
  • Substance X transfers thermal energy to substance Y through conduction. What is an accurate conclusion about the condition of bo
    5·2 answers
  • Through which material do P waves move the fastest?
    5·1 answer
  • Hi :) In a pendulum experience , what affects the period &amp; explanation too? Thank you sm :))
    11·1 answer
  • A wave has a wavelength of 45 meters and a period of 9.0 seconds. What is the frequency of the wave? 5.0 m/s 405 Hz 5.0 Hz 0.11
    5·2 answers
  • A spring stretches by 18 cm when a bag of potatoes weighing 56 N is suspended from its end. How much elastic potential energy in
    8·1 answer
  • You push a 45 kg wooden box across a wooden floor at a constant speed of 1.0 m/s. The coefficient of kinetic friction is 0.25. N
    12·1 answer
  • Look at the distance-time graph below. It shows Angela's journey as she walks to the end of the road and back. The gradient repr
    8·1 answer
  • when energy from battery was added to water, were the gases produced by this made of the same particles as those produced from h
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!