Max. Velocity... (1 Viewer)

FinalFantasy

Active Member
Joined
Jun 25, 2004
Messages
1,179
Gender
Male
HSC
2005
for example a question asks for maximum velocity where velocity;
v=-2root17 sin(@)

so i say max velocity is -2root 17
but the answer says 2root17

when it asks for max speed it's 2root17, but it asks for max velocity in here...

in some books wen it asks for max v. and it was negative(like wat i have now), the answer is negative
and wen it asks speed it is always positive
but dis one the answer is negative when it asks for velocity lol
 

acmilan

I'll stab ya
Joined
May 24, 2004
Messages
3,989
Location
Jumanji
Gender
Male
HSC
N/A
FinalFantasy said:
for example a question asks for maximum velocity where velocity;
v=-2root17 sin(@)

so i say max velocity is -2root 17
but the answer says 2root17

when it asks for max speed it's 2root17, but it asks for max velocity in here...

in some books wen it asks for max v. and it was negative(like wat i have now), the answer is negative
and wen it asks speed it is always positive
but dis one the answer is negative when it asks for velocity lol
Speed is a scalar and should always be positive and not have a direction. Velocity is a vector and should have a magnitude and direction. The + or - sign is simply showing which direction the object travels, so max velocity could be - or +, it doesnt make a difference since that sign is just an indication of which direction its travelling. So technically its max velocity would be both -2root17 and +2root17, depending on which direction it travels. Hence it doesnt make a difference so long as you in some way show you understand what velocity is in comparison to speed.
 

FinalFantasy

Active Member
Joined
Jun 25, 2004
Messages
1,179
Gender
Male
HSC
2005
yea well i had v=-2root17 sin(@)
and it ask me to find max "velocity"
so i said -2root17 but the answer is positive.
 

acmilan

I'll stab ya
Joined
May 24, 2004
Messages
3,989
Location
Jumanji
Gender
Male
HSC
N/A
FinalFantasy said:
yea well i had v=-2root17 sin(@)
and it ask me to find max "velocity"
so i said -2root17 but the answer is positive.
Well when sin@ = -1 then the velocity is also a maximum, just in the opposite direction. In the end they may have just taken the positive because of convention but negative is just as correct.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top