Solve a problem of your own!
Download the Studdy App!

Math

Math Snap

PROBLEM

(I) A 55.0-kg firefighter climbs a flight of stairs 28.0 m high at constant speed. How much work does she do?

STEP 1

1. The firefighter has a mass of 55.0kg 55.0 \, \text{kg} .
2. The height of the stairs is 28.0m 28.0 \, \text{m} .
3. The firefighter climbs at a constant speed, implying no change in kinetic energy.
4. The work done is against gravity.

STEP 2

1. Recall the formula for work done against gravity.
2. Calculate the gravitational force acting on the firefighter.
3. Substitute the values into the work formula.
4. Calculate the work done.

STEP 3

Recall the formula for work done against gravity:
W=Fd W = F \cdot d where F F is the gravitational force and d d is the distance (height) moved in the direction of the force.

STEP 4

Calculate the gravitational force acting on the firefighter:
F=mg F = m \cdot g where m=55.0kg m = 55.0 \, \text{kg} is the mass and g=9.8m/s2 g = 9.8 \, \text{m/s}^2 is the acceleration due to gravity.
F=55.0kg×9.8m/s2 F = 55.0 \, \text{kg} \times 9.8 \, \text{m/s}^2 F=539N F = 539 \, \text{N}

STEP 5

Substitute the values into the work formula:
W=Fd W = F \cdot d W=539N×28.0m W = 539 \, \text{N} \times 28.0 \, \text{m}

SOLUTION

Calculate the work done:
W=539N×28.0m W = 539 \, \text{N} \times 28.0 \, \text{m} W=15092J W = 15092 \, \text{J} The work done by the firefighter is:
15092J \boxed{15092 \, \text{J}}

Was this helpful?
banner

Start understanding anything

Get started now for free.

OverviewParentsContactPolicyTerms
TwitterInstagramFacebookTikTokDiscord