To determine how hard the dogs must pull to overcome the frictional force, we need to calculate the frictional force acting on the sled. Here's a step-by-step solution:
1. Identify the given values:
- Weight of the sled, [tex]\( W \)[/tex] = [tex]\( 2200 \)[/tex] N
- Coefficient of friction, [tex]\( \mu \)[/tex] = [tex]\( 0.15 \)[/tex]
2. Understand the relationship between frictional force and the given values:
The frictional force [tex]\( F_{\text{friction}} \)[/tex] can be calculated using the formula:
[tex]\[
F_{\text{friction}} = \mu \times N
\][/tex]
where [tex]\( N \)[/tex] is the normal force. On a flat surface, the normal force [tex]\( N \)[/tex] equals the weight of the sled, which is [tex]\( 2200 \)[/tex] N.
3. Plug in the values into the formula:
[tex]\[
F_{\text{friction}} = 0.15 \times 2200
\][/tex]
4. Calculate the result:
[tex]\[
F_{\text{friction}} = 0.15 \times 2200 = 330 \text{ N}
\][/tex]
Therefore, the dogs must pull with a force of [tex]\( 330 \)[/tex] N to overcome the frictional force and move the sled.
The correct answer is:
[tex]\[
\boxed{330 \text{ N}}
\][/tex]
