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
Aleonysh [2.5K]
3 years ago
5

A box with a mass of 70 kg sits on a slope of 40 degrees. you are tasked with pushing the box up the slope. the static (stationa

ry) coefficient of friction between the box and the slope is 0.55, and the kinematic (while moving) coefficient of friction is 0.35.
a. what is the minimum force required to keep the box from slipping?
b. what is the minimum force required to begin pushing the box up the slope?
c. what is the minimum force required to maintain the box moving up the slope?
d. what is the force required to accelerate the box up the slope at 0.65 m/s2 once it is already moving upwards? give your answers in newtons (n).
Physics
1 answer:
Scrat [10]3 years ago
5 0

PART a)

Force of friction on the box is given by formula

F_f = \mu mg cos\theta

F_f = 0.55 * 70 * 9.8 * cos40

F_f = 289 N

now the component of weight along the inclined

F_g = mgsin40

F_g = 70*9.8 * sin40

F_g = 441 N

now by force balance the force required to hold the block

F_{net} = F_g - F_f

F_{net} = 441 - 289 = 152 N

Part b)

to slide the block upwards the friction force will be upwards along the plane

F = F_g + F_f

F = 441 + 289 = 730 N

Part c)

Kinetic friction on the block is given by

F_k = \mu_k mg cos\theta

F_k = 0.35 * 70 * 9.8 * cos40

F_k = 184 N

now in order to move it up

F = F_g + F_k

F = 441 + 184

F = 625 N

Part d)

now to accelerate upwards by 0.65 m/s^2 we can use

F - F_g - F_k = ma

F - 441 - 184 = 70* 0.65

F = 670.5 N

You might be interested in
A planet has a mass of 5.68 x 1026 kg and a radius of 6.03 x 107 m. What is the weight of a 65.0 kg person on the surface of thi
Paul [167]

To solve this problem, we must know the gravitational force of the planet. The equation would be,

 F=G \frac{ m_{1} m_{2}  }{ r^{2} }

This would calculate the force between two objects with masses m1 and m2 and the gravitational constant, G, is 6.67 x 10^-11 m3 s-2 kg-1 and with r as the distance between the objects.

Thus,

F = (6.67 x 10^-11 m3 s-2 kg-1) * (5.68 x 10^26 kg) * (65 kg) * ((1/6.03 x 10^7 m)^2)

F = 678 kg/s^2 or 678 N

Answer is letter B.

4 0
3 years ago
For the hypothetical reaction A → B, calculate the average rate of disappearance of A if the initial concentration of A is 0.91
marishachu [46]

Answer:

The right answer is 8.9 x 10^-3 M/min

Explanation:

           A → B

-d [A]/dt  = K [A]

ΔA/Δt     = - (C2 -C1)/t2 - t1

               = - (0.11 - 0.91)/90

               = 8.9 x 10^-3 M/min

7 0
3 years ago
PLEASE HELP ASAP!!!!!! <br> What should each experiment only have one of? <br> variable or constant
slega [8]

Answer:

the answer should be a constant

hope this helps!!

3 0
3 years ago
Read 2 more answers
A child on a high dive has a mass of 40 kilograms. If the high dive is 10 meters in the air, what is the potential energy? GPE=m
saw5 [17]

Answer:

Ep = 3924 [J]

Explanation:

To calculate this value we must use the definition of potential energy which tells us that it is the product of mass by the acceleration of gravity by height.

E_{p}=m*g*h\\

where:

Ep = potential energy [J] (units of Joules)

m = mass = 40 [kg]

g = gravity acceleration = 9.81 [m/s²]

h = elevation = 10 [m]

E_{p} =40*9.81*10\\E_{p} = 3924 [J]

7 0
2 years ago
Care sunt marimile ce caracterizează nucleul?
Yakvenalex [24]

Answer:

Sub stratul exterior lichid-metal al miezului Pământului se află o bilă solidă de fier și aliaj de nichel cu aproximativ 1,60 km în diametru.

Explanation:

4 0
3 years ago
Other questions:
  • If the density of a diamond is 3.5 g/cm", what would be the mass of a diamond whose
    11·1 answer
  • A roller coaster starts from rest at the top ofan 18m hill.
    5·1 answer
  • A machine takes 0.5 seconds to move a brick 1 meter and put 100 Joules of energy into it. (hint: Power is the amount of energy t
    13·1 answer
  • Tomarrow last day of school
    10·1 answer
  • Lightning bolts can carry currents up to approximately 20 kA. We can model such a current as the equivalent of a very long, stra
    8·1 answer
  • The number of oscillations that a wave completes per unit of time in called its _______.
    13·1 answer
  • Hi i need help re-stating Newton's Second law. It needs to be at least two sentences.
    11·2 answers
  • Two risks of exposure to High levels of UV radiation
    10·2 answers
  • Clapping your hands is what type of energy transfer or transformation
    8·1 answer
  • F. If heat could flow to the container, how would the final temperature be affected?
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!