Physics 1 · Unit 1 · Paper 1

Kinematics unit test

A test on this unit alone, marked as a percentage and a letter grade — for the test your class is actually sitting, rather than for May. Answer everything, then submit once: seeing the answer to question 3 before attempting question 4 makes the final percentage meaningless.

Paper 1 Paper 2 Paper 3

Each paper is built from this unit’s 52 terms and is the same for everyone, so a teacher can assign “Unit 1, Paper 1” and every student sits the identical test. Multiple choice is marked objectively; the written sections you mark yourself against the model answer and rubric.

Suggested time 37 min 34 points0/17 attempted

Air resistance breaks projectile symmetry

The two roots of a projectile time equation

Acceleration

Displacement vs distance

Free fall

Speed is never negative

Reference frame

When speed increases or decreases

Average vs instantaneous velocity

Negative area under a velocity-time graph

Projectile launched at an angle

Range of a projectile

Short answer 1. Define or explain: Independence of projectile components

3 pts

Short answer 2. Define or explain: Zero velocity does not mean zero acceleration

3 pts

Short answer 3. Define or explain: Kinematic equation without displacement

3 pts

Short answer 4. Define or explain: Scalar vs vector

3 pts

Free response

10 pts

MATHEMATICAL ROUTINES (Question 1, 10 points). Water exits the nozzle of a fountain at an angle θ0 above the horizontal. At time t = 0 a droplet exits the nozzle and follows a projectile path (Figure 1), reaching a maximum height h1 above the nozzle. At t = tf the droplet returns to the height at which it exited. (Figure 2 provides axes for the horizontal and vertical velocity components versus time.) For part B: the nozzle is replaced with one of smaller radius; water exits the new nozzle at the same angle θ0, and the volume flow rate is unchanged. A droplet from the new nozzle reaches maximum height h2.

A(i). Describe (or sketch) graphs of the horizontal and vertical components of the droplet’s velocity as functions of t from t = 0 to t = tf.

A(ii). Derive an expression for the speed of the water exiting the nozzle in terms of θ0, h1, and physical constants, as appropriate. Begin with a fundamental physics principle or an equation from the reference information.

A(iii). The nozzle has a circular cross-section of radius r0. Derive an expression for the volume flow rate of the water exiting the nozzle in terms of θ0, h1, r0, and physical constants, as appropriate.

B. Indicate whether h2 is greater than, less than, or equal to h1, and justify your answer with qualitative reasoning beyond mathematical derivations or expressions.