Your Name: _______________________ PHY203

Final Exam

Student ID: ________________________ Chapters 1-12,14

12/12/02 , 3-6 p.m.

Lecture Time: 9 a.m 1p.m. 2p.m. 3p.m. Honors

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2 _________________ 8 __________________

Part 1 ____________ 9 __________________

Part 4 __________

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Total _______________

Part 2 ____________

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Part 3 ____________

3. Two blocks, (m₁ =10 kg and m₂ =20kg) are positioned as shown below. The first mass rests on a frictionless surface the second mass is suspended by a string. Assume the pulley is massless.

a. Redraw the blocks below and sketch all of the forces on each block (free body diagrams).

b. Write Newton’s force equation in both axes for both masses.

c. Calculate the magnitude of the acceleration, a, of the blocks and the magnitude of the tension in the string,T.

4. A mass of m=5 kg is attached to a string with a length of 0.5 m. The mass is then released from a horizontal position at point A, with speed v_o=5 m/s, as shown below. It swings through vertical point B and eventually encounters a spring. The spring is compressed by 5 cm until the ball comes to rest at the horizontal position at point C.

a. Using conservation of energy, calculate the velocity of the mass at point B.

b. Calculate the tension, T, in the string at point B.

c. Calculate the spring constant, k, of the spring.

PHY203

Exam #2, F/02

Crib Sheet

Chapters 4-7

(Note: Use 9.81 m/s2 for g, the acceleration due to gravity.)

For constant acceleration(in one dimension):

x_f = x_o + v_ot + (1/2)at2

v_f = v_o + at

v_f2 = v_o2 + 2a(x_f - x_o)

(Note: Bold letters indicate vectors below.)

F = ma

spring force: F = -kDx , where k is the spring constant

weight: W = mg

friction force:

kinetic fk = mkFn , where Fn is the normal force and mk is the kinetic frictional coefficient

static fs < msFn, fsmax = msFn

uniform circular motion

centripetal acceleration: a = v2/R

Work and Energy

W = F ^. d = Fdcosq

Work done by friction = -f_kDs

E_Thermal = |Work done by friction|

Kinetic Energy: K = (1/2)mv²

Potential Energy: U_spring = (1/2)kx²

U_grav = mgh

Total energy, E, is conserved ( a constant).