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
pantera1 [17]
3 years ago
10

A 21 N block rests on a horizontal surface. The coefficients of static and kinetic friction between the surface and the block ar

e μs = 0.80 and μk = 0.60. A horizontal string is attached to the block and a constant tension T is maintained in the string. What is the force of friction acting on the block for each of the following values of T?
a) T=15N

b) T=35N
Physics
1 answer:
Georgia [21]3 years ago
8 0

Answer:

a)15 N

b)12.6 N

Explanation:

Given that

Weight of block (wt)= 21 N

μs = 0.80 and μk = 0.60

We know that

Maximum value of static friction given as

Frs = μs m g = μs .wt

by putting the values

Frs= 0.8 x 21 = 16.8 N

Value of kinetic friction

Frk= μk m g = μk .wt

By putting the values

Frk= 0.6 x 21 = 12.6 N

a)

When T = 15 N

Static friction Frs= 16.8 N

Here the value of static friction is more than tension T .It means that block will not move and the value of friction force will be equal to the tension force.

Friction force = 15 N

b)

When T= 35 N

Here value of tension force is more than maximum value of static friction that is why block will move .We know that when body is in motion then kinetic friction will act on the body.so the value of friction force in this case will be 12.6 N

Friction force = 12.6 N

You might be interested in
Name and draw the circuit symbols for the
pishuonlain [190]

Answer:

here is the answer its a picture

Explanation:

7 0
3 years ago
Which statement is true about the thermal energy of an object? Choose the correct answer. 1). Thermal energy is the internal pot
Brums [2.3K]
This thermal energy flows as heat within the box and floor, ultimately raising the temperature of both of these objects.
5 0
2 years ago
What happens to electrical energy that is used by objects in our homes? (1 point) a It is absorbed by batteries. b It is destroy
Reil [10]

Question:

<em>What happens to electrical energy that is used by objects in our homes? (1 point)</em>

<em>a It is absorbed by batteries. </em>

<em>b It is destroyed. </em>

<em>c It is stored in solar panels. </em>

<em>d It is transformed into other forms of energy.</em>

<em />

Answer:

D

3 0
2 years ago
Read 2 more answers
The current in a series circuit is 19.3 A. When an additional 7.40-Ω resistor is inserted in series, the current drops to 13.4 A
Bogdan [553]

Answer:

16.8ohms

Explanation:

According to ohm's law which states that the current passing through a metallic conductor at constant temperature is directly proportional to the potential difference across its ends.

Mathematically, V = IRt where;

V is the voltage across the circuit

I is the current

R is the effective resistance

For a series connected circuit, same current but different voltage flows through the resistors.

If the initial current in a circuit is 19.3A,

V = 19.3R... (1)

When additional resistance of 7.4-Ω is added and current drops to 13.4A, our voltage in the circuit becomes;

V = 13.4(7.4+R)... (2)

Note that the initial resistance is added to the additional resistance because they are connected in series.

Equating the two value of the voltages i.e equation 1 and 2 to get the resistance in the original circuit we will have;

19.3R = 13.4(7.4+R)

19.3R = 99.16+13.4R

19.3R-13.4R = 99.16

5.9R = 99.16

R= 99.16/5.9

R = 16.8ohms

The resistance in the original circuit will be 16.8ohms

5 0
3 years ago
A person is standing on a scale in an unmoving elevator. The elevator starts to move upwards at 1 m/s squared. Is the scale read
timama [110]

Answer: GREATER

Explanation:when elevator does not move it reads weight of the person . when elevator moves up let apparent weight be F . W acts downwards so net force is F-W

HENCE

F-W =ma

F= ma+W

AS a= 1 m/s^2

F = m (1)+W

HENCE GREATER

7 0
2 years ago
Other questions:
  • A mass is measured as 6.2 kg in one experiment and as 6.20 kg in another. in what way do these measurements differ​
    11·1 answer
  • a person exerts a force of 55 n on the end of a door 74 cm wide. what is the magnitude of the torque if the force is exerted?
    15·1 answer
  • Why is it important for scientists to share information from their investigation?
    8·1 answer
  • A young lady can paddle a canoe in a lake 7.7 m/s. She paddles downstream in a river whose current is 12.4 m/s. What is the comb
    10·1 answer
  • A coaxial cable consists of an inner conductor with radius ri = 0.20 cm and an outer radius of ro = 0.4 cm and has a length of 1
    14·1 answer
  • What’s pasta used for?
    7·2 answers
  • a 55 kg baseball player slides into third base with an initial speed of 4.6 m/s If the coefficient of kinetic friction between t
    14·1 answer
  • Which statement is correct about the equation for work?
    10·1 answer
  • A 200 g mass is placed on the meter stick 20 cm from the fulcrum. An
    9·1 answer
  • Say you were at mission control on
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!