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
34kurt
3 years ago
13

A worker pushed a 25.0 kg block 6.50 m along a level floor at constant speed with a force directed 30.0° below the horizontal. I

f the coefficient of kinetic friction between block and floor was 0.410, what were (a) the work done by the worker's force and (b) the increase in thermal energy of the block-floor system?
Physics
1 answer:
Kipish [7]3 years ago
8 0

Answer:

a) 855.41J

b) 855.41J

Explanation:

The force equation is

N - mg - F sinθ = 0

N = mg + F sinθ

The frictonal  force is =

F_x = F cos \theta

U_xN = Fcos\theta

substitute the value of the normal force in the above equation

U_x (mg + Fsin\theta ) = F cos\theta

F = \frac{U_x mg}{cos\theta - U_x sin\theta } \\\\= \frac{0.41 \times 25 \times 9.8 }{cos 30^\circ- 0.41 \times sin30 ^\circ}

= 151.96N

a) work done = F × d

= (151.96) × (6.5) cos30°

= 855.41 J

b) The increase in thermal energy of the block floor system will be equal to the work done by the worker

work done = F × d

= (151.96) × (6.5) cos30°

= 855.41 J

You might be interested in
what would the net force be on the box in the problems shown below.( both force and direction).​ for all four diagrams. please e
DIA [1.3K]

Answer:
A) object moves 20 N [West] or -20 N [East]
B) object moves 6 N [South] or -6 N [North]
C) object moves 90 N [West] or -90 N [East]
D) object does not move and is at rest*

*Rest means 0


Why:

A)both forces from north and south that are pushing against the object neutralize each other. Assume that north is positive and south is negative: 20 [N] + (-20) [S] = 0
On West and east, you can see that west has a greater force. Assume that west is negative and east is positive: 50 [E] + (-70) [W] = -20 [E]
8 0
3 years ago
What two properties show that the drink is a fluid ( girl drinking fruit punch out of a clear glass cup with a straw.)
Ainat [17]
It takes the shape of the cup and it can be sucked through a straw 
3 0
3 years ago
Read 2 more answers
A cannon is fired horizontally at 243 m/s off of a 62 meter tall, shear vertical cliff. How far in meters from the base of the c
Alekssandra [29.7K]

Answer:

865.08 m

Explanation:

From the question given above, the following data were obtained:

Initial velocity (u) = 243 m/s

Height (h) of the cliff = 62 m

Horizontal distance (s) =?

Next, we shall determine the time taken for the cannon to get to the ground. This can be obtained as follow:

Height (h) of the cliff = 62 m

Acceleration due to gravity (g) = 9.8 m/s²

Time (t) =?

h = ½gt²

62 = ½ × 9.8 × t²

62 = 4.9 × t²

Divide both side by 4.9

t² = 62/4.9

Take the square root of both side.

t = √(62/4.9)

t = 3.56 s

Finally, we shall determine the horizontal distance travelled by the cannon ball as shown below:

Initial velocity (u) = 243 m/s

Time (t) = 3.56 s

Horizontal distance (s) =?

s = ut

s = 243 × 3.56 s

s = 865.08 m

Thus, the cannon ball will impact the ground 865.08 m from the base of the cliff.

6 0
3 years ago
PLEASE HELP!!
defon
The right answer is A
7 0
3 years ago
5. During an anti-bullying club meeting after school, a student mentions that a new student has joined your class at school. The
Oksana_A [137]

Answer:

a. Constant gossiping, and talking negative about a student could cause them to feel very very ill about their beliefs, their familly, school, clothes, etc. this  scenario will make the student feel alienated.

b. The club should advise the students that they should not participate in these talks, allow them into their groups, and should try to talk people out of those conversations.

c. The advice will keep several kids pull away from talking negatively about the kid, help stop the ill intended gossip, and hopefully make them feel better.

5 0
3 years ago
Other questions:
  • What is the main purpose of trying to quickly cool heated food?
    6·2 answers
  • Laissez-faire situations are characterized by a high degree of government involvement (t or <br> f.
    7·2 answers
  • ONLY TWO ANSWER CHOICES!!
    8·1 answer
  • How does the total amount of energy change as the spring goes up and down?
    13·1 answer
  • EXPLAIN CONSERVATION OF MOMEMTUM WITH THE HELP OF COLLISION OF TWO OBJECT.
    13·1 answer
  • Do only number 3 and thank
    9·1 answer
  • If you can answer my last post ill give you 75 points pls its very important and please make sure it correct!!!!!!!
    5·2 answers
  • 56. What is the range of magnitudes that can be attained from the
    9·1 answer
  • A 0.6 m length of current carrying wire is placed in a uniform magnetic field oriented perpendicularly to the wire. The current
    10·1 answer
  • To which end of the horseshoe magnet will the north end of the magnet be attracted
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!