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nmoren13
Sep 25, 2011, 12:08 PM
A rock is thrown downward from the top of a 40m tower with an initial speed of 12m/s. If gravity = 9.8m/s^2 and air resistance is negotiable, what is the speed of the rock just before hitting the ground?

nmoren13
Sep 25, 2011, 12:11 PM
A motorist traveling at 110km/hr is being chased by a police car at 130km/hr. If the police
Car starts from 1 kilometer back, how long does it take the police to intercept the motorist?

nmoren13
Sep 25, 2011, 12:13 PM
A toy rocket, launched from the ground, rises vertically with an acceleration of 20m/s^2
For 2 when it runs out of fuel. Disregarding air resistance, how high will the rocket
Rise>

nmoren13
Sep 25, 2011, 12:22 PM
If the displacement, X, of an object is related to velocity, V, according to the relation
X = A v, the constant A has the dimension of what>

nmoren13
Sep 25, 2011, 12:25 PM
Using dimensional analysis, which one of the following is correct?
(a----------> m/s^2 , v---------->m/s , x----------->m)

A. V--->2ax

B. X^2--->2av

C. T--->sqrt 2x/a

D. X---> v/t

nmoren13
Sep 25, 2011, 12:28 PM
The ratio are at which paint can be sprayed from a spray gun may be expressed as R= a/t^2.
If are is measured in m^3/s, and time is measured in seconds, what are the units of "a"?

nmoren13
Sep 25, 2011, 12:33 PM
A bullet traveling horizontally at a speed of 350m/s hits a board perpendicular to the surface,
Passes through it, and it emerges on the other side at a speed of 210m/s. If the board
Is 4cm thick, how long does the bullet take to pass through it ( in seconds)?

nmoren13
Sep 25, 2011, 12:34 PM
A jet aircraft being launched from an aircraft carrier is accelerated from rest along a 94m track
For 25s. What is the launched speed of the jet?

nmoren13
Sep 25, 2011, 12:36 PM
A v versus t graph is drawn for a ball moving in one direction. The graph starts at the origin
And at t=5s the acceleration of the ball is zero. We know that at t=5s,

A. The slope of the curve is non-zero
B. The velocity of the ball is not changing
C. The curve is not crossing the time axis
D. The curve is at v=0, t=0

nmoren13
Sep 25, 2011, 12:38 PM
If vector A= -5.0x-4.0y and vector B= -3.0x+8.0y, then the magnitude of vector C=A-B
Is what?

Curlyben
Sep 25, 2011, 12:41 PM
Please refer to this announcement:

Do not simply retype or paste a question from your book or study material

We won't do your homework questions for you.
You were given the assignment for you to learn.

If you come up with your own answer and post it for us to critique that is within reason.

If you have some SPECIFIC questions that you couldn't find or didn't understand, we may help with that.
But this is your assignment, so show us you have at least attempted to complete it on your own.

Thank you.

nmoren13
Sep 25, 2011, 12:42 PM
Three vectors, expressed in Cartesian coordinates, are

x-comp y-comp
S 3.0 0.0
T -4.9 4.9
U -3.0 -5.2

The orientation of the vector S-T-U ( in degrees) is
A. 1.6
B. 176.4
C. 183.4
D. 358.4

jcaron2
Sep 25, 2011, 07:07 PM
Nmoren13, please don't post more than one question per thread.

Second, we're here to HELP you with your homework, not to do it FOR you. If you're truly stuck on every single one of those problems, then let us know which part of each question you're having trouble with. We can guide you along, but it's going to be up to you to get the answers.

Unknown008
Sep 25, 2011, 10:49 PM
All your questions have to do with kinematics. I assume you have a problem with the topic in itself. I will advise you to take your notes and read them, and give all those questions a try. Where you are stuck, post everything you did up to where you got stuck.

It is impossible that you were given those questions as homework if you haven't done the topic at school yet.

TUT317
Sep 26, 2011, 12:03 AM
Some good advice has been given above.

The first one you could try.

V^= u^+2gd

The next one you could try

V1=130kph V2=110 kph

S1=V1t S2=V2t S2=s1 -1


Perhaps you could also try for the rest at

The Physics Classroom (http://www.physicsclassroom.com)


Tut