Question

A box with mass 1 kg slides down an inclined plane for a distance of 1m. The inclined plane makes an angle of 30° with the grFrom the choices given below. choose the correct magnitude and direction of the center of mass of the system of particles shoMagnitude: approx. 1.85 m Direction: 45° from X axis direction Magnitude: approx. 0.85 m Direction: 45° from X axis directionA1500-kg elevator car moves 40.0 m above the ground at constant speed. (a) What is the work done on the lift by the gravitatiI need all 3 questions please

0 0
Add a comment Improve this question Transcribed image text
Answer #1

1.

work done is given by,

W = F*d*cos(A)

here, F = force = friction force

F = \mu *N

d = distance travelled = 1 m

A = angle between F & d = 180 deg

where,\mu = 0.5

N = normal force = m*(g*cos\theta)

given \theta = inclined angle = 30 deg

m = mass = 1 kg

So, N = 1*9.8*cos(30 deg) = 8.5

then, W = 0.5*8.5*1*cos(180 deg)

W = -4.25 J

therefore correct option is B. Approximately -4.2 J

2.

Center of mass is given by:

In x-direction

Xcm = (m1x1 + m2x2 + m3x3)/(m1 + m2 + m3)

In y-direction

Ycm = (m1y1 + m2y2 + m3y3)/(m1 + m2 + m3)

m1 = 2 kg, (x1, y1) = (0,0)

m2 = 2 kg, (x2, y2) = (1, 0)

m3 = 2 kg, (x3, y3) = (0, 1)

m4 = 4 kg, (x4, y4) = (1, 1)

Now

Xcm = (2*0 + 2*1 + 2*0 + 4*1)/(2+2+2+4) = 0.6 m

Ycm = (2*0 + 2*0 + 2*1 + 4*1)/(2+2+2+4) = 0.6 m

Center of mass will be at (Xcm, Ycm) = (0.6, 0.6) m

So, magnitude of distance of center of mass from origin = d = sqrt(0.6^2 + 0.6^2)

d = 0.8485 m = approx. 0.85 m

direction of center of mass = \theta = arctan(Ycm/Xcm) = arctan(1/1)

\theta = 45 deg from X axis direction

therefore correct option is B.

Magnitude : approx. 0.85 m

Direction : 45 deg from X axis direction

Please upvote.

Add a comment
Know the answer?
Add Answer to:
I need all 3 questions please A box with mass 1 kg slides down an inclined...
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for? Ask your own homework help question. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions
  • A 100-kg block slides up or down a frictionless inclined plane that makes an angle of...

    A 100-kg block slides up or down a frictionless inclined plane that makes an angle of 30°. What is the acceleration of the block on the x-direction (parallel to the plane)? What is the magnitude of the normal force on the block?How would the acceleration change if friction is present?

  • a box with a mass of m = 3.25 kg on a surface inclined at an...

    a box with a mass of m = 3.25 kg on a surface inclined at an angle of 35.0°. The coefficient of static friction between the box and the surface is 0.330. Find the minimum magnitude of the force F (in N), applied to the box in a direction perpendicular to the surface, that will prevent the box from sliding down the surface.

  • Mi A mass M slides-downward along a rough plane surface inclined at angle = 29.21 in...

    Mi A mass M slides-downward along a rough plane surface inclined at angle = 29.21 in degrees relative to the horizontal. Initially the mass has a speed Vo = 7.68 m/s, before it slides a distance L = 1.0 m down the incline. During this sliding, the magnitude of the power associated with the work done by friction is equal to the magnitude of the power associated with the work done by the gravitational force. What is the coefficient of...

  • A block of mass 4.4 kg slides 18 m from rest down an inclined plane making...

    A block of mass 4.4 kg slides 18 m from rest down an inclined plane making an angle of 22 o with the horizontal. If the block takes 10 s to slide down the plane, what is the retarding force due to friction?

  • A mass M slides downward along a rough plane surface inclined at angle \Theta\: Θ =...

    A mass M slides downward along a rough plane surface inclined at angle \Theta\: Θ = 29.8 in degrees relative to the horizontal. Initially the mass has a speed V_0\: V 0 = 5.32 m/s, before it slides a distance L = 1.0 m down the incline. During this sliding, the magnitude of the power associated with the work done by friction is equal to the magnitude of the power associated with the work done by the gravitational force. What...

  • A mass M slides downward along a rough plane surface inclined at angle \Theta\: Θ =...

    A mass M slides downward along a rough plane surface inclined at angle \Theta\: Θ = 31.7 in degrees relative to the horizontal. Initially the mass has a speed V_0\: V 0 = 6.9 m/s, before it slides a distance L = 1.0 m down the incline. During this sliding, the magnitude of the power associated with the work done by friction is equal to the magnitude of the power associated with the work done by the gravitational force. What...

  • A 12 kg block begins from rest and slides down an inclined plane. After 10s the...

    A 12 kg block begins from rest and slides down an inclined plane. After 10s the block has a velocity of 18 m/s. The plane's angle of Inclination is .524 radians. What is the coefficient of friction between the plane and block? What is the Kenetic energy of the block at t=15s? What is the total work done by all the forces acting on the block after it slides down the plane for a distance of 1m?

  • A mass m = 1 kg slides down a θ = 30◦ inclined plane from a...

    A mass m = 1 kg slides down a θ = 30◦ inclined plane from a height of 5 m. At the bottom of the incline, it collides with another mass M = 3 kg, and the latter is initially at rest as shown in Fig. 3. The surface to the right of the inclined plane on which the 3 kg (green) mass sits is horizontal. (a) The inclined surface is frictionless. Conserve energy to find the velocity of the...

  • N MA) m. A inclined to to a 30° ta plane kg goes goes up Al...

    N MA) m. A inclined to to a 30° ta plane kg goes goes up Al point A = 2 m/s the and return to point A with v= 1 m/s mar) > up and by goes up a) Find the work done th b) If Me for What diolence travel the mass until hit velocity is FRN up to the plane ceco voolm/s mass m=2kg goes up to 300 inclined plane. 130 At point Å VA-2m/s, the mass goes...

  • mi 13) A block with mass m = 5.00 kg is placed on an inclined plane...

    mi 13) A block with mass m = 5.00 kg is placed on an inclined plane with slope of a = 30.0° and is connected to a hanging block with mass m2 = 3.00 kg by a cord passing over a small, frictionless pulley as shown in the figure to the right. The coefficient of static friction is 0.333, and the coefficient of kinetic friction is 0.150. What is the magnitude and direction of the friction force on block mı?

ADVERTISEMENT
Free Homework Help App
Download From Google Play
Scan Your Homework
to Get Instant Free Answers
Need Online Homework Help?
Ask a Question
Get Answers For Free
Most questions answered within 3 hours.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT