All categories

3 years ago

15. Calculate The coefficient of kinetic friction be-

Physics

1 answer:

allochka39001 [22]3 years ago

3 0

Answer:

Wt = 26.84 [N]

Explanation:

In order to solve this problem we must use the definition of work in physics. Which tells us that this is equal to the product of force by distance.

In this case, we must sum the works of the force applied by the box and the friction force that also acts on the box.

The friction force is defined as the product of the normal force by the coefficient of friction.

f = N*μ

where:

N = normal force = m*g [N] (units of Newtons)

m = mass = 72 [kg]

g = gravity acceleration = 9.81 [m/s²]

f = friction force [N]

μ = friction coefficient = 0.21

f = 72*9.81*0.21

f = 148.32 [N]

Now the total work:

Wt = WF - Wf

where:

Wt = total work [J] (units of Joules)

WF = work by the pushing force [J]

Wf = work done by the friction force [J]

Wt = (160*2.3) - (148.32*2.3)

Wt = 26.84 [N]

Note: The friction force exerts a negative work, because this force is acting in opposite direction to the movement, therefore the negative sign.

You might be interested in

If a car is moving to the left with constantvelocity, one can conclude thatthere mustbe no forces applied to the car.the netforc

Allisa [31]

Answer:

the net force applied to the car is zero.

Explanation:

According to Newton's second law, the acceleration of an object (a) is directly proportional to the net force applied (F):

$a=\frac{F}{m}$

where m is the object's mass.

In this problem, the car is moving with constant velocity: this means that the acceleration is zero, a = 0. Therefore, according to the previous equation, the net force must also be zero: F = 0. So, the correct answer is

the net force applied to the car is zero.

3 0

3 years ago

The main benefit you receive from using locomotor movements in a variety of activities is?

adell [148]

Answer:The locomotor skills include: walking, running, skipping, galloping, hopping, jumping, sliding, walking backwards, and leaping. Students are learning these skills at it could take lots of practice to develop the skills necessary to complete all of the locomotor skills.

Explanation:

7 0

3 years ago

10 turns of wire are closely wound around a pencil as shown in the figure. when measured using a scale as shown, the length of t

Mila [183]

Answer:

a. The thickness of the wire is 2.5 mm.

b. The wire is 0.25 cm thick.

Explanation:

Number of turns of the wire = 10

The length of total turns = 25 mm

a. The thickness of the wire can be determined by;