PHYSICS 231
1st Midterm, October 17, 1997, 5:30 pm - 6:30 pm
Instructor: P. Q. Hung

Do all problems (20 points each). READ them carefully. You have to EXPLAIN all your answers. DO NOT just write them down. ANSWERS WITHOUT EXPLANATION WILL BE GIVEN NO CREDIT.

Useful formulas:

x=x₀+v_0xt+(1/2)a_xt²

y=y₀+v_0yt+(1/2)a_yt²

v_x=v_0x+a_xt

v_y=v_0y+a_yt

$v_{f}^2 = v_{i}^2 + 2 a \Delta x$

$R = (v_{0}^{2}/g) sin(2\theta_{0})$

$\sum {\vec{F}}_{i} = m \vec{a}$

$f_{s, max} = \mu_s N$

$f_k = \mu_k N$

g=9.8m/s²