Physics HELP!

posted by .

A block of mass 3 kg slides along a horizontal surface while a 20-N force is applied to it at an angle of 25°. If needed, use g = 10 m/s2. For a coefficient of kinetic friction of 0.3 between the block and the surface, the frictional force acting on the block is most nearly

9 N
8.5 N
15 N
6 N
12 N

  • Physics HELP! -

    friction=mu*mg=.3*3*10 N

  • Physics HELP! -

    Is the 25 degree angle of the applied force above or below horizontal? It makes a big difference in the answer.

  • Physics HELP! -

    If the angle is 25 degree below the horizontal, then the upward component makes the friction lighter (less normal force).

    friction=mu(normal force)
    = .3(mg-20sin25)
    =.3(30-8.45)
    = no answer.

    so assuming the 25 is above the horizontal, friction will be greater..
    friction= = .3(mg+20sin25)
    =.3(38.45)= almost 12 N

  • Physics HELP! -

    F(y) = F•sinα =20•sin25º =8.45 N.
    The force may be applied
    \ from top downward
    or / from the bottom upward ,
    then
    F(fr) =μ•N = μ•[mg ± F(y)] =
    = 0.3•{3•10 ± 8.45) =
    = 11.54 N or 6.5 N,

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. physics

    The coefficient of static friction between a block and a horizontal floor is 0.40, while the coefficient of kinetic friction is 0.15. The mass of the block is 5.0 kg. A horizontal force is applied to the block and slowly increased. …
  2. physics

    The coefficient of static friction between a block and a horizontal floor is 0.40, while the coefficient of kinetic friction is 0.15. The mass of the block is 5.0 kg. A horizontal force is applied to the block and slowly increased. …
  3. physics

    The coefficient of static friction between a block and a horizontal floor is 0.40, while the coefficient of kinetic friction is 0.15. The mass of the block is 5.0 kg. A horizontal force is applied to the block and slowly increased. …
  4. physics

    The coefficient of static friction between a block and a horizontal floor is 0.414, while the coefficient of kinetic friction is 0.107. The mass of the block is 4.03 kg. A horizontal force is applied to the block and slowly increased. …
  5. Physics

    An block of mass , starting from rest, slides down an inclined plane of length and angle with respect to the horizontal. The coefficient of kinetic friction between the block and the inclined surface is . At the bottom of the incline, …
  6. physics

    An block of mass m , starting from rest, slides down an inclined plane of length L and angle θ with respect to the horizontal. The coefficient of kinetic friction between the block and the inclined surface is μ1 . At the …
  7. physics

    An block of mass m , starting from rest, slides down an inclined plane of length L and angle θ with respect to the horizontal. The coefficient of kinetic friction between the block and the inclined surface is μ1 . At the …
  8. physics

    1. A 100N block lies on a frictional surface. A force of 50N was applied horizontally where the block had moved 5 m from the positive direction. Find the work done by the applied force and the work done by the weight of the block. …
  9. Physics

    A force of 12.7 N pulls horizontally on a 1.4-kg block that slides on a rough, horizontal surface. This block is connected by a horizontal string to a second block of mass m2 = 2.32 kg on the same surface. The coefficient of kinetic …
  10. PHYSICS

    A 6.53-kg block initially at rest is pulled to the right along a horizontal surface by a constant force of 125 N applied at an angle θ above the horizontal. The coefficient of kinetic friction between the block and the horizontal …

More Similar Questions