Kinematics

Question 1

Velocity= v

Answer 1

displacement/time= change in displacement/change in time

Question 2

Acceleration= a

Answer 2

velocity/time= change in velocity/change in time

Question 3

Big 5 for Uniform accelerated motion

Answer 3

a=constant

1. d=1/2(v +v)t
2. v= v initial + at
3. d= v initial(t) + 1/2a(t squared)
4. d= v final(t) - 1/2 a(t squared)
5. v final(squared)= v initial(squared) + 2ad
   * * equation 2, 3 and 5 are most frequently used on MCAT**

Question 4

An object has an initial velocity of 3m/s and a constant acceleration of 2m/s2 in the same direction. What is the velocity after 6 seconds? *** which equation to use?

Answer 4

equation 2

v=v initial +at

Question 5

A particle has an initial velocity of 10 m/s and a constant acceleration of 3 m/s2 in the same direction. How are does it go? *** what equation to use?

Answer 5

equation 3

d= v initial(t) + 1/2 a(t squared)

Question 6

An object starts form rest and travels in a straight line with an acceleration of 4 m/s2 in the same direction until it reaches a velocity of 20m/s. What distance does it travel? *** what equation to use?

Answer 6

equation 5

v squared= v initial squared + 2ad

Question 7

A particle has the initial velocity of 6 m/s and moves with a constant acceleration in the same direction for 5 seconds until the final velocity is 16 m/s. How are did it travel? *** what equation to use?

Answer 7

equation 1

d= 1/2 (v +v)t

Question 8

An object has a final velocity of 24 m/s and travels for 4 seconds at an acceleration of 2 m/s2. What distance does it travel?*** what equation to use?

Answer 8

equation 4

d= velocity final(t) +1/2a(t squared)

Question 9

distance vs time graph

What is the slope?

Answer 9

velocity

Question 10

velocity vs time graph

what is the slope?

Answer 10

acceleration

Question 11

An object is dropped from a height of 80 m/s. What time does it take to hit the ground. *** what equation to use?

Answer 11

a=g=10m/s
equation 3
v initial =0
d=1/2 a(t squared)

Question 12

An object is dropped from a height of 80 m. what is its final velocity? *** what equation to use?

Answer 12

equation 5

v squared= v initial squared + 2ad

Question 13

A ball is thrown straight up, with an initial speed of 30m/s. How high does it go? *** what equation to use?

Answer 13

equation 5

v squared= v initial squared +2ad

Question 14

A ball of mass 10kg and a ball of mass 1 kg are dropped at the same time from 45 m. Which ball hits the ground first and how long does it take. Air resistance is ignored. *** what equation to use?

Answer 14

Will hit at the same time. Mass not a factor.
Equation 2
v initial = 0
d= 1/2 a(t squared)

Question 15

Projectile motion

What is the velocity of the horizontal and vertical components?

Answer 15

vertical:
**a=0 therefore velocity is constant
vx=vcos(theta)

horizontal:
vy= vsin(theta) + gt

Question 16

Projectile motion

what is the displacement of the vertical and horizontal components?

Answer 16

vertical:
x=vcos(theta)t

horizontal:
y=vsin(theta)t +1/2g(t squared)

Question 17

Projectile motion

What is the acceleration of the horizontal and vertical components

Answer 17

vertical:
a=0

horizontal:
a=g=10 m/s (round up for MCAT)

Question 18

Angle: Sin
0
30
45
60
90

Answer 18

0 = 0
30 = 1/2 square root 1= 0.5
45= 1/2 square root 2= 0.7
60= 1/2 square root 2= 0.85-0.87
90= 1

Question 19

Angle: Cos
0
30
45
60
90

Answer 19

0= 1
30= 1/2 square root 2= 0.85-0.87
45= 1/2 square root 2= 0.7
60 = 1/2 square root 1= 0.5
90 = 0

Question 20

A cannon ball is shot from ground level at an initial velocity of 100m/s at an angle of 30 degrees form the ground. How high does it go?*** what equation to use?

Answer 20

MUST FIND TIME FIRST!!!!

vy final= vy initial + (-g)t

note: only the going up of the ball therefore:
vy final =0
acceleration is negative because going up

Question 21

A cannon ball is shot from ground level at an initial velocity of 100m/s at an angle of 30 degrees form the ground. What is the velocity at the balls highest point?*** what equation to use?

Answer 21

vy=0
vx is constant
vx=vxcos(theta)

Question 22

A cannon ball is shot from ground level at an initial velocity of 100m/s at an angle of 30 degrees form the ground. What is the total flight time?*** what equation to use?

Answer 22

vy=vy initial + (-g)t
* once found t only half flight time therefore
t(total)= 2t

Question 23

A cannon ball is shot from ground level at an initial velocity of 100m/s at an angle of 30 degrees form the ground. How are does the ball travel?*** what equation to use?

Answer 23

x= vxcos(theta) x t(total)

Question 24

A projectile is launched form 5 m with an initial velocity of 80 m/s at 40 degrees to the horizontal. If v horizontal is v1 after 1 second and v horizontal is v2 after 2 seconds, what is the value of v2-v1?

Answer 24

v horizontal is constant therefore v1=v2 and v2-v1=0

Question 25

A rock is thrown horizontally from a cliff with an initial velocity of 10 m/s. It strikes the ground 5 seconds later. What is the height of the cliff? *** what equation to use?

Answer 25

vy initial=0

d=1/2a(t squared)

Question 26

A rock is thrown horizontally from a cliff with an initial velocity of 10 m/s. It strikes the ground 5 seconds later. How are from the cliff does the ball land? *** what equation to use?

Answer 26

x= vx initial x time

Question 27

A ball is kicked form ground level, travels up then down and hits the ground in 4 seconds. If v horizontal is 20 m/s, how high did the ball go?*** what equation to use?

Answer 27

y= vy initial (time) + 1/2 a(t squared)