Posted by **Jack Hill** on Sunday, July 15, 2012 at 4:21pm.

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?

- Science -
**Elena**, Sunday, July 15, 2012 at 4:58pm
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

## Answer This Question

## Related Questions

- Physics - A 4.0 x 101 kg wind sled is gliding East across a frozen lake at a ...
- physics - A wind sled has a mass of 45kg and is gliding at a speed of 2m/s over ...
- Physics - An iceboat is at rest on a frictionless frozen lake when a sudden wind...
- Physics/Math - An iceboat is at rest on a frictionless frozen lake when a sudden...
- physics - A model sailboat is slowly sailing west across a pond at 0.342 m/s. A ...
- physics - A model sailboat is slowly sailing west across a a pond at.33m/s. a ...
- Physics - A 60 kg ice skater holds up a large sheet of cardboard that can catch ...
- Physics - A 60 kg ice skater holds up a large sheet of cardboard that can catch ...
- Physics - A 60 kg ice skater holds up a large sheet of cardboard that can catch ...
- English - 1. He died young. 2. He died when he was young. 3. When he was young, ...

More Related Questions