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
dexar [7]
2 years ago
14

A 10 kg box initially at rest is pulled with a 50 N horizontal force for 4 m across a level surface. The force of friction actin

g on the box is a constant 20 N. How much work is done by the normal force pushing up on the box from the ground?
A. 10 J
B. 0 J
C. 100 J
D. 50 J
Physics
1 answer:
emmasim [6.3K]2 years ago
5 0

Answer: 0 j

Explanation:

It is given that,

Mass of the box, m = 10 kg

Force with which the box is pulled, F = 50 N

It is moved a distance of 4 m

Force of friction acting on the box, f = 20 N

We need to find the initial kinetic energy the box have. It is clear that the box is at rest initially. As there is no motion in the box at that time. The formula for the kinetic energy of the box is given by :

As v = 0

So, the initial kinetic energy of the box is 0. Hence, this is the required solution.  

You might be interested in
Which among the following statement/s is correct?
seropon [69]

Answer:

(D) None

Explanation:

The force of gravity is the force pulling every element of matter together. The more the matter the higher the force of gravity.

Examples of this force at work are;

  • The force that causes an apple to fall from the tree
  • The force that causes a rock to roll downside a hill
  • The force causing people to walk on the earth surface instead of floating

The force that facilitates a pen on your hand to write on a paper is friction force between the pen and the paper. Gravitational force acts downwards thus force applied on an object beside you is not the force of gravity.

8 0
2 years ago
You weigh 580 N on Earth. If you were to go to Mars, where its gravitational pull is 3 . 7 11 m /s 2 , what would you weigh? (Hi
andrew-mc [135]

Answer:

59.18 kg

Explanation:

use f=ma

f= 580 N

a = 9.8 m/s 2

weigh(m) doesn't change only force(F) changes

7 0
2 years ago
Read 2 more answers
Melting, freezing, and boiling are______ changes
avanturin [10]
Melting, boiling, and freezing are state changes!
Hope this helps! Any questions please just ask! Thank you so much!
6 0
3 years ago
Read 2 more answers
What is pressure in physics ​
harkovskaia [24]
Pressure is the force per unit area. This means that the pressure a solid object exerts on another solid surface is its weight in newton’s divided by its area in square metres
8 0
3 years ago
Let the four horizontal compass directions north, east, south, and west be represented by units vectors n^, e^, s^, and w^, resp
Marrrta [24]

Answer:

c = e > b = d > a

Explanation:

Given vectors are all unit vectors, therefore they have a magnitude of 1

<h3>Let a, b be two vectors and magnitude of cross product of these two vectors is (magnitude of a) × (magnitude of b) × (sine of angle between these two vectors)</h3>

As all are unit vectors their magnitude is 1 and therefore in this case the cross product between any two vectors depends on the sine of angle between those two vectors

In option a as both the vectors are same, the angle between them will be zero and sin0° will also be 0

In option b angle between those two vectors is 135° and sin135° is 1 ÷ √2

In option c angle between those two vectors is 90° and sin90° is 1

In option d angle between those two vectors is 45° and sin45° is 1 ÷ √2

In option e angle between those two vectors is 90° and sin90° is 1

So by comparison of magnitudes of cross products in each option, the order will be  c = e > b = d > a

5 0
3 years ago
Other questions:
  • How many grams does 15.58 L of gasoline weigh? Gasoline has a density of 0.74 g/mL
    11·1 answer
  • Please Please Please Can Help Me On This Question!!!!! I Give Thanks!!!!
    5·1 answer
  • scientific __________ involves the knowledge and understanding necessary for evaluating information, making personal decisions,
    10·2 answers
  • A very thin 19.0 cm copper bar is aligned horizontally along the east-west direction. If it moves horizontally from south to nor
    8·1 answer
  • Which is not true of the Intertropical Convergence Zone?A) It features heavy precipitation B) It's where the trade winds collide
    9·1 answer
  • A positive charge is moved from one point to another point along an equipotential surface. The work required to move the charge:
    6·1 answer
  • Please help! A net force of 2.0 N acts on a 2.0-kg object for 10 seconds. What is the object’s kinetic energy after that 10 seco
    9·1 answer
  • The Earth moving round the Sun in a circular orbit is acted upon by a
    8·1 answer
  • Denisty is found by what equation
    9·2 answers
  • A mimibus drives with a constant speed of 39 km/h. how far can it travel in 1.94 hours?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!