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
Reika [66]
3 years ago
14

A child does 350 J of work while pulling a box from the ground up to his tree house at a steady speed with a light rope. The tre

e house is above the ground. What is the mass of the box
Physics
1 answer:
777dan777 [17]3 years ago
4 0

Answer:

8.929kg

Explanation:

The work done to place the box at tree house=350 J.

The distance from ground to tree house =4.0 m and g=9.8m/s^2

E=mgh\\\\m=350J/(9.8m/s^2\times 4.0m)\\\\m=8.929kg

Hence the mass of the box is 8.929kg

You might be interested in
A piece of solid copper, at 10oC, is dropped into a graduated cylinder of 100°C water. Which statement BEST describes the change
enot [183]

Answer:

D

Explanation:

just took the test

6 0
3 years ago
Read 2 more answers
This force can either push the block upward at a constant velocity or allow it to slide downward at a constant velocity. The mag
Dmitry [639]

Answer:

Part a)

F = 135.7 N

Part b)

F = 62.5 N

Explanation:

Part a)

If block is sliding up then net force must be zero and friction will be in opposite to the direction of motion of the block

Fcos\theta = mg + F_f

Fsin\theta = F_n

so we have

Fcos\theta = mg + \mu(Fsin\theta)

F(cos\theta - \mu sin\theta) = mg

F = \frac{mg}{cos\theta - \mu sin\theta}

F = \frac{55}{cos50 - 0.310(sin50)}

F = 135.7 N

Part b)

If block is sliding down then net force must be zero and friction will be in opposite to the direction of motion of the block

Fcos\theta = mg - F_f

Fsin\theta = F_n

so we have

Fcos\theta = mg - \mu(Fsin\theta)

F(cos\theta + \mu sin\theta) = mg

F = \frac{mg}{cos\theta + \mu sin\theta}

F = \frac{55}{cos50 + 0.310(sin50)}

F = 62.5 N

6 0
3 years ago
At a point 1.2 m out from the hinge, 14.0 N force is exerted at an angle of 27 degrees to the moment arm in a plane which is per
geniusboy [140]

Answer:

\tau = 7.63 Nm

Explanation:

As we know that moment of force is given as

\tau = \vec r \times \vec F

now we have

\vec r = 1.2 m

\vec F = 14 N

now from above formula we have

\tau = r F sin\theta

here we know that

\theta = 27 degree

so we have

\tau = (1.2)(14) sin27

\tau = 7.63 Nm

3 0
3 years ago
Find the lengths of each of the following vectors
Irina18 [472]

Answer:

Explanation:

Generally, length of vector means the magnitude of the vector.

So, given a vector

R = a•i + b•j + c•k

Then, it magnitude can be caused using

|R|= √(a²+b²+c²)

So, applying this to each of the vector given.

(a) 2i + 4j + 3k

The length is

L = √(2²+4²+3²)

L = √(4+16+9)

L = √29

L = 5.385 unit

(b) 5i − 2j + k

Note that k means 1k

The length is

L = √(5²+(-2)²+1²)

Note that, -×- = +

L = √(25+4+1)

L = √30

L = 5.477 unit

(c) 2i − k

Note that, since there is no component j implies that j component is 0

L = 2i + 0j - 1k

The length is

L = √(2²+0²+(-1)²)

L = √(4+0+1)

L = √5

L = 2.236 unit

(d) 5i

Same as above no is j-component and k-component

L = 5i + 0j + 0k

The length is

L = √(5²+0²+0²)

L = √(25+0+0)

L = √25

L = 5 unit

(e) 3i − 2j − k

The length is

L = √(3²+(-2)²+(-1)²)

L = √(9+4+1)

L = √14

L = 3.742 unit

(f) i + j + k

The length is

L = √(1²+1²+1²)

L = √(1+1+1)

L = √3

L = 1.7321 unit

3 0
3 years ago
When an object is balanced about a pivot, the total clockwise moment must be equal to the total __________ __________. What two
Keith_Richards [23]

Answer:

When an object is balanced, about a pivot, the total clockwise moment must be equal to the total anticlockwise moment about that pivot.

Hope that helps.

5 0
3 years ago
Other questions:
  • Explain what relative weight is and why it is important to the calculation of atomic mass.
    5·1 answer
  • A goose waddles 18.0 m north and then 5.00 m east. He then walks 2.00 m south and 2.00 m west. What is the magnitude and directi
    10·1 answer
  • When two or more forces act together on an object what do they combine to form
    6·1 answer
  • What can help a scientist identify any object in a group of objects?
    8·2 answers
  • A turbine of a coal burning installation delivers 1,500 hp of mechanical energy to a generator. The generator then converts 80.0
    8·1 answer
  • In fig. 30.11, suppose that and with switch open, switch is left closed until a constant current is established. then is closed
    14·1 answer
  • Scientific laws explain_____.
    5·2 answers
  • Must all species reproduce in order for the species to survive?
    9·2 answers
  • Sand dunes during the Dust Bowl are an example of:
    15·1 answer
  • Can someone explain it with steps?
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!