finding pulling force: 7.35cos10 up the plane
finding pulling normal force: 7.35sin10 upwards
finding total normal force; 12sin20-7.35sin10
finding friction= mu*(above normal force)
work done by pulling: 7.35cos10*2
work absorbed by friction: mu(above normal force)*2
KE= workdonebypulling-workabsorbedby friction.
A steel block weighing 12N is pulled up an incline plane 20° above the horizontal by a constant force of 7.35 N which makes an angle of 10° above the inclined plane. The block stars from rest and is pulled 2.0m along the inclined plane. the coefficient of friction between the block and inclined plane is 0.20.find the increase in kinetic energy of the block?
6 answers
- gain in potential energy due to going up
damon is correct. change this to read...
finding pulling force: 7.35cos10 up the plane
finding pulling normal force: 7.35sin10 upwards
finding total normal force; 12sin20-7.35sin10
finding friction= mu*(above normal force)
work done by pulling: 7.35cos10*2
work absorbed by friction: mu(above normal force)*2
gain in PE: 12*2*sin20
KE= workdonebypulling-workabsorbedby friction-gain in PE
finding pulling force: 7.35cos10 up the plane
finding pulling normal force: 7.35sin10 upwards
finding total normal force; 12sin20-7.35sin10
finding friction= mu*(above normal force)
work done by pulling: 7.35cos10*2
work absorbed by friction: mu(above normal force)*2
gain in PE: 12*2*sin20
KE= workdonebypulling-workabsorbedby friction-gain in PE
Fp = 12*sin20 = 4.1 N. = Force parallel with incline,
Fn = 12*Cos20 - 7.35*sin10 = 10 N. = Normal force,
Fk = u * Fn = 0.2 * 10 = 2 N.,
F = 7.35*Cos10 - Fp - Fk = 7.24 - 4.1 - 2 = 1.14 N. = Net force,
Work = F * d = 1.14 * 2 = 2.28 J. = Increase in KE.
Fn = 12*Cos20 - 7.35*sin10 = 10 N. = Normal force,
Fk = u * Fn = 0.2 * 10 = 2 N.,
F = 7.35*Cos10 - Fp - Fk = 7.24 - 4.1 - 2 = 1.14 N. = Net force,
Work = F * d = 1.14 * 2 = 2.28 J. = Increase in KE.
Yes
2.27j