What is the relation of mass and power?

Click For Summary
SUMMARY

The discussion focuses on calculating power using the relationship between mass, distance, and time. The initial approach involves using the formula W = Fx, where force is derived from mass multiplied by gravitational acceleration (9.8 m/s²), followed by applying P = W/t to find power. A specific example is provided where a 50 kg woman runs uphill over a height of 5 m in 3 seconds, illustrating the need for additional details such as the incline angle to accurately determine power. The conclusion emphasizes that while the method is generally correct, complete information is essential for precise calculations.

PREREQUISITES
  • Understanding of Newton's Second Law (F = ma)
  • Familiarity with the concepts of work (W = Fx)
  • Knowledge of power calculations (P = W/t)
  • Basic principles of gravitational force (9.8 m/s²)
NEXT STEPS
  • Research the effects of incline angles on power calculations
  • Learn about friction and its impact on work and power
  • Explore efficiency in mechanical systems and its relevance to power output
  • Study advanced kinematics to understand motion under varying forces
USEFUL FOR

Students in physics, engineers calculating mechanical power, and fitness professionals analyzing energy expenditure during physical activities.

Generally Confused
Messages
9
Reaction score
0
How should power be calculated in a situation where distance and time are both given, as well as mass. At first, I was thinking of just using W=Fx (force as mass x 9.8) to solve for work, and then I would take the solution for work and put it into P=wt.

Does this make sense? That's my best guess, but I'd really appreciate if you could tell me whether or not I am handling mass correctly.
 
Physics news on Phys.org
Generally Confused said:
How should power be calculated in a situation where distance and time are both given, as well as mass. At first, I was thinking of just using W=Fx (force as mass x 9.8) to solve for work, and then I would take the solution for work and put it into P=wt.

Does this make sense? That's my best guess, but I'd really appreciate if you could tell me whether or not I am handling mass correctly.

You haven't given enough information to be able to tell. For example if an object of mass 2 kg is located 3 m away for a time of 4 s, then I've been given mass, distance, and time. But I need more details to be able to determine the work done and the power developed.
 
Mister T said:
You haven't given enough information to be able to tell. For example if an object of mass 2 kg is located 3 m away for a time of 4 s, then I've been given mass, distance, and time. But I need more details to be able to determine the work done and the power developed.

Alright. So take a woman weighing about 50kg running uphill. If the hill is 5m, how much power would be required for her to reach the top in 3 seconds? (Sorry, this is sort of a bad example, but I figured it kind of demonstrates the format.) Does the process I explained work for this?
 
Generally Confused said:
Alright. So take a woman weighing about 50kg running uphill. If the hill is 5m, how much power would be required for her to reach the top in 3 seconds?

still not enough info

what is the angular incline of the hill ?
is the 5m you state the height of the hill or the length of the incline slope ?
 
Generally Confused said:
Alright. So take a woman weighing about 50kg running uphill. If the hill is 5m, how much power would be required for her to reach the top in 3 seconds? (Sorry, this is sort of a bad example, but I figured it kind of demonstrates the format.) Does the process I explained work for this?

Assuming an altitude of 5 m, yes; ignoring friction and assuming she's 100% efficient.
 

Similar threads

Undergrad 3D Printed Piston | Lower mass = Power
  • · Replies 41 ·
2
Replies
41
Views
4K
Undergrad Mechanical power generated by a force F
  • · Replies 41 ·
2
Replies
41
Views
4K
Undergrad Power required to reach X velocity in X time with drag
  • · Replies 10 ·
Replies
10
Views
2K
Undergrad Is there a list of root-power quantities? Or a rule of thumb?
  • · Replies 14 ·
Replies
14
Views
2K
Graduate Inconsistency between definitions of power and work in continuum mechanics?
  • · Replies 9 ·
Replies
9
Views
1K
Graduate 100% energy efficient, constant power rocket
  • · Replies 25 ·
Replies
25
Views
4K
Undergrad A problem regarding power output in cycling
  • · Replies 7 ·
Replies
7
Views
1K
Undergrad Gravitational potential energy
  • · Replies 46 ·
2
Replies
46
Views
5K
Undergrad Acceleration as a Function of Time Using Constant Power
  • · Replies 27 ·
Replies
27
Views
4K
Undergrad What is the correct way to calculate the power required to lift a mass?
  • · Replies 25 ·
Replies
25
Views
11K