Posted by **kayla** on Thursday, February 2, 2012 at 7:27pm.

A person pushes a 17.0 kg lawn mower at constant speed with a force of 74.0 N directed along the handle, which is at an angle of è = 48.0° to the horizontal

(b) Calculate the horizontal retarding force on the mower

(c) Calculate the normal force exerted vertically upward on the mower by the ground.

(d) Calculate the force the person must exert on the lawn mower to accelerate it from rest to 1.3 m/s in 2.0 seconds (assuming the same retarding force).

- physics -
**Henry**, Saturday, February 4, 2012 at 6:25pm
Wm = mg = 17kg * 9.8N/kg = 166.6 N. =

Wt. of mower.

Fm = 166.6 N @ 0 Deg. = Force of mower.

Fp = 166.6*sin(0) = 0. = Force parallel

to gnd.

Fv = 166.6*cos(0) = 166.6 N. = Force

perpendicular to Gnd. = Normal.

b. Fn = Fap-Fp-Fr = 0,

74*cos48-0-Fr = 0,

49.52-Fr = 0,

Fr = 49.52 N. = Retarding force.

c. Fv = mg = 166.6 N.

d. a = (Vf-Vo)/t,

a = (1.3-0) / 2 = 0.65 m/s^2.

Fcos48-Fr = ma,

Fcos48-49.52 = 17*0.65 = 11.05,

Fcos48 = 11.05+49.52 = 60.57,

F = 60.57 / cos48 = 90.5 N.

## Answer This Question

## Related Questions

- Ap physics - A person pushes a 15.0 kg lawn mower at constant speed with a force...
- Physics - A person pushes a 11.0 kg lawn mower at constant speed with a force of...
- physics - forces - A person pushes a 16.0 kg lawn mower at constant speed with a...
- physics - A person pushes a 14.0-kg lawn mower at constant speed with a force of...
- physics - A person pushes a 11.0 kg lawn mower at constant speed with a force of...
- physics - A person pushes a 10.0 kg lawn mower at constant speed with a force of...
- 12th grade Physics - A boy pushes a lawn mower with a mas of 17.9 kg starting ...
- physics - A person pushes a 14.5 kg lawnmower at constant speed with a force of ...
- physics - A woman pushes a lawn mower with a con- stant force of 112 Newtons at ...
- Physics - A woman pushes a lawn mower with a con- stant force of 112 Newtons at ...

More Related Questions