Little help please?? which is a vector and a scalar?

Question

imagine that i have an exam 2morrow but no books!! coz our school didn't provide us with books...so i have 2 ask my questions here on yahoo answers

i know 9/44 questions for my exam soo please please help me

classify into vectors and scalars

i know what they are just classify don't explain please

impluse, weigth, mass, position , heat, pressure, area, velocity, work , force, power , time and distance

thanks in advance and tell me WHTHER U R SURE OR not ,,,cuz again i have an exam

impulse, wight, mass, position, heat, pressure, area , velocity,

Answer 1

A scalar is a number used to measure something.  15 degrees Fahrenheit, 28 apples, and so on.  There's usually a distinction made between a number (6, for instance, or pi) and a scalar (6 beans, pi feet), but not always.

A vector, in physics at least, is a scalar with a direction added.  32 feet north, 5 meters per second down, things like that.

Just ask yourself - does direction make sense with this thing?  Generally, if so, it's a vector.  If not, it's a scalar.

There are some quantities which can be both, depending on how you look at them.  For instance, velocity is a vector.  If you're traveling 100 miles per hour north, that's your velocity.  Sometimes, though, the direction is unimportant.  If a cop stops you for speeding, he's not going to be particularly impressed with the fact that you were traveling the right way.  What he's concerned about is that you were going too fast.  When you don't care about the direction, it's called speed.  Speed is the magnitude of velocity.  Magnitude means the quantity without the direction.  Some terms:

distance - scalar

displacement - vector

speed - scalar

velocity - vector

Acceleration is a vector, but sometimes you don't care about the direction.  In that case, there is no special word for it.  You simply refer to the magnitude of the acceleration.

Impulse is a vector.  Weight is a vector (down).  Mass is a scalar.  Position can be either - distance and displacement, see above.  Heat is a scalar.  Pressure is a scalar.  Area is a scalar.  Velocity is a vector.  Work is a scalar.  Force is a vector.  Power is a scalar.  Time is a scalar.  Distance (as I said) is a scalar.  It's the magnitude of displacement.