Question

You kick a ball with a speed of 4 m/s at an angle of 10 degrees. How far away does the ball land?
A: 0.40m
B: 0.56m
C: 0.95m
D: 0.79m

Answer 1

there's a simpler approach for this one, we just need to figure out how long the ball spent in the air and then use the x-velocity to calculate the distance

so vf = vi + at

where vf is 0, vi is the initial velocity in the y-direction, a is the acceleration due to gravity, and solve for t

Answer 2

0=4+-9.8(t)

Answer 3

we have to resolve the velocity into it's y-component, so velocity * sin(theta) not just velocity

Answer 4

4sin(10)

Answer 5

so 4sin(10)+(-9.8)t

Answer 6

good, set that equal to 0 and solve for t

Answer 7

0=4sin(10)+(-9.8)t

Answer 8

i got 0.07

Answer 9

good, so the ball stays up to 0.07 * 2 seconds (since that equation only tells us how long it takes to reach the peak, not the entire distance)

so distance = velocity * time

this time use the x-direction velocity and time to find the distance

Answer 10

so 0.07*2?

Answer 11

that's the time

use that to find the distance in the x direction

Answer 12

0.56

Answer 13

B

Answer 14

awesome