# Math Help - questions in physics

1. ## questions in physics

1 ) what will happend to the value of resultant when

a ) vector A add to B and they are in the same directions and same magnitude ?
b ) vector A add to B and they are in the opposite directions and equal magnitude ?
c) vector A add to B and they are in the same directions and unequal magnitude ?
d) vector A add to B and they are in the opposite directions and unequal magnitude ?

a = resultant will be sum of two vectos
b= resultant = 0
c=resultant will be sum of two vectos
d=resultant will be sum of two vectos

2 ) a car traveling towards north is suddenly braked . What is the directiom of its accleration ?

.... towards north

3 ) A basball dropped from the roof of ball building. it take 3 seconds to hit the ground . The height of the building is

vo = 0
a = -9.81
t=3

now v = v0 + at
= 0+(-9.81)(3) = -29.43

now the height is Dx = v^2-V0 /2(a)
= 44.145

2. 1. We spell 'vectors' and not 'vectos' Good though. I would point out that for d, the directions are not to be neglected, that is one of the forces will bear a negative sign.

2. If the car accelerates North... wouldn't it speed up towards the North?

3. You can use a single formula for that...

$s = v_ot + \frac12 at^2$

$s = 0(3) + \frac12 (-9.81)(3)^2 = 44.145 m$

Good. Only number 2 needs to be reviewed.