Posted by **Rhea** on Wednesday, November 17, 2010 at 7:39pm.

A 63 canoeist stands in the middle of her canoe. The canoe is 3.0 long, and the end that is closest to land is 2.6 from the shore. The canoeist now walks toward the shore until she comes to the end of the canoe. Suppose the canoeist is 3.3 from shore when she reaches the end of her canoe.

What is the canoe's mass?

- Physics -
**bobpursley**, Wednesday, November 17, 2010 at 7:50pm
Well, the cg did not move.

The cg is (1.5+2.6) from shore at the start.

cg*totalmass= 3.3*63+masscanoe*(3.3+1.5)

(1.5+2.6)(63+masscanoe)= 3.3*63+masscanoe(4.8)

masscanoe(4.1-4.8)=3.3*63-4.1**63

solve for mass canoe

- Physics -
**Tavis**, Tuesday, November 23, 2010 at 4:23pm
better to sum torques about the center of mass.

from standing in the middle of the canoe we know that the CM is at x = 1.5+2.6 = 4.1

when the person is 3.3m from the shore that makes them (4.1m-3.3m)=0.8m from the CM and because we know the canoe is 3m long the CM of the canoe is (3.3+1.5)=4.8m from the shore and consequently (4.8m-4.1m)=0.7m from the CM of the system.

now sum the torques about the CM and set equal to zero with CCW rotation as being positive we get

0=(63kg)*(0.8m)-(Mcanoe)*0.7m

Mcanoe=(0.8/0.7)*63kg

## Answer This Question

## Related Questions

- Physics - A 63 kg canoeist stands in the middle of her 22kg canoe. The canoe is ...
- Physics - A 63 kg canoeist stands in the middle of her 19 kg canoe. The canoe is...
- Physics - A 74-kg canoeist stands in the middle of her 18-kg canoe. The canoe is...
- Physics - A 9.6 kg dog takes a nap in a canoe and wakes up to find the canoe has...
- Physics - A 9.6 kg dog takes a nap in a canoe and wakes up to find the canoe has...
- Physics - A 8.5 dog takes a nap in a canoe and wakes up to find the canoe has ...
- physics - A man with a mass of 64.1 kg stands up in a 61-kg canoe of length 4.00...
- Physics - A 30-kg child stands at one end of a floating 20-kg canoe that is 5.0-...
- PHYSICS - PLEASE HELP - A 9.6 kg dog takes a nap in a canoe and wakes up to find...
- physics - A man with a mass of 58 kg stands up in a 69-kg canoe of length 4.0 m ...

More Related Questions