Sph4u Assignment 1.pdf

Name: _____________________________________________

SPH4U- Kinematics Assignment Due Date: Monday, May 7, 2018

5 extra communication marks are awarded based on the organization of your assignment, therefore all answers should show full work; all graphs and sketches should be clearly labeled. If you need to use additional paper for your work, please write your name on the top of each page. 1. A cat is moving at 18 m/s when it accelerates at 4 m/s2 for 2 seconds. What is his new velocity? 
[2 K] 2. Isaac throws an apple straight up (in the positive direction) from 1.0 m above the ground, reaching a maximum height of 35 meters. Neglecting air resistance, what is the ball’s velocity when it hits the ground? 
[2 K] 3. A driver of a car going 90 km/h suddenly sees the lights of a barrier 40.0 m ahead. It takes the driver 0.75 s before he applies the brakes (this is known as reaction time). Once he does begin to brake, he decelerates at a rate of 10.0 m s2 . Does he hit the barrier? [3 T] 4. While strolling along on Planet X an astronaut decides to throw a hammer and a feather upwards at 5.0 m/s. They both return to the point of release in 3.0 s. What is the acceleration due to gravity on Planet X? [2 A]

Name: _____________________________________________ TRANSFORMING GRAPHS OF MOTION 5. The middle graph below shows the velocity of a hypothetical object moving in a The middle graph below shows the velocity of a hypothetical object moving along a straight line. straight line. a. can What can we say about the motion of this object? [1 C] 1. What we say about the motion of this object? b. thePlot the corresponding graphs of displacement and acceleration as functions 2. Plot corresponding graphs of displacement and acceleration as functions of time. of time. [5 A]

displacement (m)

+25

0 5

10

15

20

25

time (s)

30

5

10

15

20

25

time (s)

30

5

10

15

20

25

time (s)

30

-25

velocity (m/s)

+5

0

-5

acceleration (m/s2)

+1

0

-1



physics.info

Name: _____________________________________________ 6. A swimmer heads directly across a river swimming at 1.6 m/s relative to still water. She arrives at a point 40 m downstream from the point directly across the river, which is 80 m wide. Determine: a. the speed of the current; [2 A] b. the magnitude of the swimmer's resultant velocity; [3 T] c. the direction of the swimmer's resultant velocity; [1 T] d. the time it takes the swimmer to cross the river. [2 K] 7. A golfer hits a ball from horizontal ground in the direction of a 12 m tree, which is 80 m from the golfer. The hit gives a ball an initial velocity of 45 m/s, at an angle of 20° to the horizontal. Will the ball pass over the tree or hit it? [3 T]





8. A helicopter is travelling horizontally at 20 m/s, at a height of 50 m above a point P on horizontal ground, when it releases a package. a. How long will it take the package to reach the ground? [1 K] b. How far from P will the package land? [1 K] c. Calculate the vertical velocity of the package when it reaches the ground. [2 K] 9. Explain why the average speed is always greater than or equal to the magnitude of the average velocity for an object moving in two dimensions. Give an example in your answer. [2 C] 10. What does subtracting vectors mean physically? Provide an example with your answer. [2 C]

Knowledge

Thinking /10



Application /10



Communication /10

/10