# What would affect horsepower more: speed or mass?

1. Apr 22, 2015

### Min

I was wondering which would cause the horsepower to increase and why would it be that one.

2. Apr 22, 2015

### phinds

Huh? Speed is something you GET from horsepower. Mass is something that horsepower has to overcome to get speed.

3. Apr 22, 2015

### Noctisdark

Hello min,
Horsepower is just another way of saying much power
1 Horsepower = 756 Watt
And in mechanics P = F.v so independant from mass

4. Apr 22, 2015

### SteamKing

Staff Emeritus
Actually, 1 HP = 746 watts

And there are several different ways to calculate horsepower requirements. P = F × v is one of those ways, but what if F is itself a function of v ?

For example, in fluid drag, F is proportional to v2.

5. Apr 23, 2015

### Noctisdark

Oops sorry ididn't notice that careless mistake,
@SteamKing, P = F.v regarless of whatever F is, (ie function of anything) but that a great thing to point at
Is meant to write it that way to show that it is prop to the velocity, however in cases of gravity F depends on mass and in most other cases don't but it will always depends on the velocity.