# Physics

posted by .

Pepper pulls a 20.0 kg object along the floor accelerating at 2 m/s/s, and μ = .2. How much work has he done while pulling the string 5.0 m? If it takes her 1.0 seconds, how much power has she used? If 1.0 kcal = 4184 J, and an Oreo has 50 kcal, how many Oreos did Pepper have to eat to get the above done?

• Physics -

a. Wo = mg = 20kg * 9.8N/kg = 196 N. =
Wt. of object.

Fo = 196N @ 0 Deg. = Force of object.
Fp = 196*sin(0) = 0 = Force parallel to
floor.
Fv = 196*cos(0) = 196 N. = Force perpendicular to floor.

Fn = Fap - Fp - Fk = ma,
Fap - 0 - 0.2*196 = 20*2,
Fap -0 - 39.2 = 40,
Fap = 40 + 39.2 = 79.2 N. = Applied force.

W = Fap * d = 79.2*5 = 396 Joules.

b.P=Fap*V=79.2 * 5m/s=396 J/s=396 W.

c. 0.396kJ * 239cal/kJ = 94.64 cal.

Oreos = 94.64cal * 1 Oreo/50cal = 1.9.

NOTE: An oreo cookie cannot have 50kcal(50.000 cal). I used 50 cal. in my calulation.

## Similar Questions

1. ### Physics

i know this is alot to ask for but these 10 i can nott get out of the 30 A man pulls a 10-kg box across a smooth floor with a force of 71 newtons at an angle of 23 degrees and for a distance of 97 meters. How much work, to the nearest …
2. ### physics

Two objects are connected by a light string passing over a light, frictionless pulley as in the diagram. m1 = 4.50 kg, m2 = 2.10 kg, and h = 4.30 m. The 4.50 kg object is released from rest at a point 4.30 m above the floor. Determine …
3. ### physics

An object of mass 10 kg is pulled along a horizontal floor of a distance 3 m. The friction force between the object and the floor is 50 N. What is the minimum work done by the pulling force?
4. ### Physics

Pepper pulls a 20.0 kg object along the floor accelerating at 2 m/s/s, and μ = .2. How much work has he done while pulling the string 5.0 m?
5. ### Static Fricition

An object of mass 2k is placed on the edge of the floor of a merry go round of radius 4 meters. The coefficient of static friction is 0.4 for the floor and the object. 1.How much work (in joules) is done on the object by the static …
6. ### physics

A 20-N horizontal force pushes an object along a rough floor so that the object moves with a constant velocity of 7.0 m/s. How much power does this force deliver to the object?
7. ### Physics

An object of mass .550kg is lifted from the floor to a height of 3.5m at a constant speed. How much work is done by the lifting force (include units)?
8. ### Saint Joseph's high school

An elevator can lifts 10 people up 12 floors. Each person weighs approximately 60 kg. each floor is 3m high, and it takes 15s to reach the 12th floor from the ground floor without stopping. How much work does the elevator do?
9. ### Physics

I need help with these two. 1. A horizontal force pulls a 20-kg box across the floor with constant speed. μs is 0.60, how much work does F do in moving the cart 3.0 m?
10. ### physics

A 25-kg child sits at the top of a 4-meter slide. After sliding down, the child is traveling at 5 m/s. How much PE does he start with?

More Similar Questions