# Physics

posted by .

A 4.0 x 101 kg wind sled is gliding East across a frozen lake at a constant speed of 12 m/s,
when a gust of wind from the southwest exerts a constant force of 1.0 x 102 N on its sails
for 3.0 s. With what velocity will the sled be moving after the wind has subsided?

• Physics -

p=mv=40•12 =480 kg•m/s.
F=100 N,
Δt=3 s.
Impulse = F•Δt=100•3=300 kg•m/s.
p is directed to the East
F•Δt=p1 is directed to the northeast.
p and p1 make the angle α=45º
Another angle in the parallelogram of momenta is [360-(2•45)]/2=135º
Use cosine law
p(net) =sqrt(p²+p1²-2p•p1•cos α) =
=sqrt(480²+ 300² -2•480•300•cos 135º)=
=sqrt(480²+ 300² +2•480•300•0.707)= 723.9 kg•m/s.
v=p(net)/m =723.9/40=18.1 m/s

## Similar Questions

1. ### Physics/Math

An iceboat is at rest on a frictionless frozen lake when a sudden wind exerts a constant force of 212 N, toward east, on the boat. due to the angle of the sail, the wind causes the boat to slide in a straight line for a distance of …
2. ### Physics

An iceboat is at rest on a frictionless frozen lake when a sudden wind exerts a constant force of 220 N, toward east, on the boat. due to the angle of the sail, the wind causes the boat to slide in a staraight line for a distance of …
3. ### physics

A model sailboat is slowly sailing west across a a pond at.33m/s. a gust of wind blowing at 28 degrees south of west gives the sailboat a constant acceleration of magnitude .30m/s squared during the time interval 2.0 sec. if the net …
4. ### Physics

A 60 kg ice skater holds up a large sheet of cardboard that can catch the wind and drive her (frictionlessly) across the ice. While she's moving at 0.5 m/s, a wind that is constant and horizontal for 5.0 s exerts a force on the cardboard …
5. ### Physics

A 60 kg ice skater holds up a large sheet of cardboard that can catch the wind and drive her (frictionlessly) across the ice. While she's moving at 0.5 m/s, a wind that is constant and horizontal for 5.0 s exerts a force on the cardboard …
6. ### Physics

A 60 kg ice skater holds up a large sheet of cardboard that can catch the wind and drive her (frictionlessly) across the ice. While she's moving at 0.5 m/s, a wind that is constant and horizontal for 5.0 s exerts a force on the cardboard …
7. ### physics

A wind sled has a mass of 45kg and is gliding at a speed of 2m/s over the frozen lake with neglible frictional effects. A gust of wind behind the sled exerts a force of 10N over a distance of 30m. With what speed is sled moving after …
8. ### Science

A 4.0 x 101 kg wind sled is gliding East across a frozen lake at a constant speed of 12 m/s, when a gust of wind from the southwest exerts a constant force of 1.0 x 102 N on its sails for 3.0 s. With what velocity will the sled be …
9. ### physics

A model sailboat is slowly sailing west across a pond at 0.342 m/s. A gust of wind blowing at 28.7° south of west gives the sailboat a constant acceleration of magnitude 0.305 m/s2 during a time interval of 1.87 s. If the net force …
10. ### Physics

a 60-kg ice skater holds up a large sheet of cardboard that can catch the wind and drive her (frictionlessly) across the ice. while she's moving at 0.5m/s, a wind that is constant and horizontal for 5.0s exerts a forward force on the …

More Similar Questions