Kinematics
If a ball is being whirled on a string in a horizontal circle and the string suddenly snaps, what path does the ball take?
straight (tangent to the inital)
A student pushes a crate with a constant force of 50 N over a distance of 5 meters. How much work is done?
250 J
An object is moving in a circle at a perfectly constant speed of 5 m/s. Is the object accelerating?
duhh
At the very peak of a projectile’s trajectory (thrown straight up), what is its instantaneous velocity and its instantaneous acceleration?
velocity: 0m/s
acceleration: -9.8m/s^2
A 4 kg bowling ball is moving at 3 m/s. What is its Kinetic Energy?
18 J
When you drop a pendulum in front of your face and let it swing. Why doesn't it smash to your face.
You can't generate energy from nothing.
You are driving a car and enter a sharp turn. If you maintain a constant speed but the turn gets "sharper" (the radius of the curve decreases), what happens to the velocity?
you need to slow down bcs
a=v^2/r
When a roller coaster goes through a vertical loop, why do you feel "heavier" at the bottom and "lighter" at the top?
bcs there's less normal force at the top due to centripetal acceleration
A 0.5 kg bird is perched on a branch 10 meters high. If it falls, what is its Gravitational Potential Energy relative to the ground?
49 J
A traveler holds a heavy suitcase while waiting for a bus. Then, they walk at a constant velocity for 50 meters on level ground. In which scenario is more work being done on the suitcase by the traveler?
Two students of equal mass climb the same flight of stairs. Student A sprints up in 5 seconds, while Student B walks up in 15 seconds. Who performed more work? and who used more power (extra 100)
same.
Student B used more power
A car enters a turn with a radius of 20 m at a speed of 10 m/s. What is its centripetal acceleration?
5m/s^2