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saructk
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Homework Statement
Homework Equations
F=ma
fk=μR
The Attempt at a Solution
What's wrong in my work? Is a(B) not equal to a(A)? Why?
swsw said:There is no guarantee to my answer but here goes:
Friction of ground on B is μk*N (where N is normal force of ground on block B which is equals to weight of B, 40Newtons)
This gives friction as 8N.
The force on A would be 100N (weight of A)
This is an atwood machine problem. First think of block A and B as on the same plane, A on left and B on right. Force on A to the right (weight) is 100N and friction on B (to the left) is 8N, giving a net force of 92N to right.
Using F=ma, find a (acceleration of the two blocks, it has to be the same for each block) [This is taking m as total mass of blocks A and B which is 140N/9.81 (taking g as 9.81)].
My acceleration is about 0.64466ms-2.
Using V=U+at ( V is final speed, U is initial speed, a is acceleration and t is time)
speed after 0.5s is 2.32233ms-1.
Hope this helps. I cannot guarantee that my solution is correct, but in my opinion it should be.
Friction is a force that opposes the motion of an object. It occurs when two surfaces come into contact with each other and resist each other's movement.
Friction can slow down or stop an object's motion, or it can cause an object to heat up due to the energy lost during the interaction between the surfaces.
Pulleys are used to change the direction of a force and make it easier to lift or move heavy objects. They can also reduce the amount of friction between the object and the surface it is moving on.
Cords are used to transmit force between two objects, such as in a pulley system. They can also be used to increase or decrease the amount of force needed to move an object.
Friction can be reduced by using lubricants or smoother surfaces, such as wheels or ball bearings, to minimize the contact between two surfaces. Additionally, applying a force in the opposite direction of the friction can also help to reduce its effects.