PHYS-1100 Fall 2009 Final Exams Answer Key

PHYS-1100 Fall 2009 Final Exams Answer Key - Tuesday Dec 8...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Tuesday Dec 8 Exam: Questions from Chapter 7, and other material not included on previous exams: 1. When a 750 gram, spherical object, of radius 2 cm, falling vertically through air of density 1.2 kg/m 3 is experiencing a drag force due to air resistance of about 9 N, it is a) moving at its terminal velocity b) moving slower than its terminal velocity, and slowing down # c) moving faster than its terminal velocity, but slowing down d) moving faster than its terminal velocity, and speeding up e) moving slower than its terminal velocity, but speeding up 2. Which of the following physical properties influences the drag coefficient of an object? a) the density of the fluid through which the object moves # b) the shape of the object c) the mass of the object d) all of the above (a-c) influence the drag coefficient e) none of the above (a-c) influence the drag coefficient 3. When an asteroid of diameter 100 meters, whose mass is about 3 x 10 9 kg, traveling through space at speed of about 9 km/s slams into our planet, it will deliver a blow whose energy is about a) 10 13 J # b) 10 17 J c) 10 22 J d) 10 26 J e) none of the above are even remotely close to correct note: a megaton (the unit of measure of a nuclear weapon's energy) is roughly equivalent to 4 x 10 15 J 4. A 12 kg object, initially moving with a speed of 2.0 m/s is accelerated to 5.0 m/s while only two forces are acting on it. One of the forces performs an amount of work equal to 74 J on it. How much work was done by the other force? a) + 74 J b) + 126 J c) + 52 J # d) + 200 J e) none of the above are even approximately correct
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
5. To merge onto the interstate highway you need to accelerate your 1500 kg car from about 30 mph (13.4 m/s) to 70 mph (31.3 m/s) within the length of a merging lane that is 250 m long. Approximately what average power is required from your car's engine? ( Recall that 746 W = 1 hp ) a) less than 30 hp b) about 51 hp # c) about 72 hp d) more than 100 hp e) not enough information is given 6. A banked 150 m radius highway curve is designed for a speed of 30 mph (13.4 m/s). Approximately what is the required angle of banking? a) about 23 degrees b) about 16 degrees c) about 11 degrees # d) about 7 degrees d) none of the above are even approximately correct 7. When a crate is dragged up a hill along a rough footpath with a rope, there are several forces and/or force components acting on the crate, namely: A: the tension in the rope B: the gravitational force C: the normal component of the path's force D: the frictional component of the path's force Which of those forces or force components DO NOT do any work on the crate? a) B # b) C c) D c) B & D e) B & C
Background image of page 2
8. How much work is done on a 22 kg object that, in an elapsed time of 10 s, moves from the origin of an xy coordinate system to the point ( x = 16, y = 12) meters while acted upon by a single force ˆ ˆ 4i 7 N F j =− G ?
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 06/07/2011 for the course PHYS 1100 taught by Professor Giomanico during the Spring '08 term at LSU.

Page1 / 18

PHYS-1100 Fall 2009 Final Exams Answer Key - Tuesday Dec 8...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online