Recent content by purduegrad

I have the equation (t-3)u2(t) - (t-2)u3(t) and they want the inverse laplace transformation of this. So basicially I drew out the unit step graph. And i had 0<t<2 --->0; 2<t<3 ---> t-3 and t>3 ----> -1. So then I just did wrote out the laplace transformations and I got (s-3)[(-e^-3s)/s +...

I'm still not following how to get that 4.45 answer, can you please elaborate for me?

I'm being asked to compute the uncertantity of air density that i calculated using pv=nrt. I have a uncertainty of .1 on the barometer, and .5 degrees for temperature, but the equation in my fluid mechanics book is too complicated. I can't draw what they're trying to say. The formula has to do...

yeah but I am not given any information about times

5280 feet in mile

hmm well its supposedly like 4.45%, i have a feeling this has something to do with partial derivatives?

Here's the problem: A magazine publishes lateral acceleration capability from cars it tests. Measurements are made using a 150' diameter skidpad, the vehicle path deviates from the circle +/- 2 ft and the vehicle speed is read from a fifth wheel sensor measuring the system to +/- .5 mph. Then...

i dunno, I am confused, lol we just need accel, i was going to use Newtons f=ma

well doing lots of problems for finals and posting the ones i can't get...again I am havin trouble with this reflection stuff A solar sail of area A=200m^2 is at a distance 1.46e8 km from the sun. suppose the power of the sun is 10^20 kw and the sail is perfectly reflecting ( think you use...

a 10^4 kg spaceship with a perfectly reflecting mirror is pushed by a laser beam with an accel of .3% g ( Earth's gravity). what is the power of the laser beam? [note:intensity*A = power] not sure what the perfectly reflecting means...but maybe someonce can help...

A real image is formed by a converging lens. It is three times higher than the object and inverted. the object and image are 1.00m apart. what is the focal length of the lens? I assume 3 = the magnitude...the 1.00 m is confusing me since its the total distance i tried using 1/p + 1/i =...

Tried this problem for about 2 hrs and no dice... A spy satellite orbiting at 150 km above the Earth's surface has a lens with a focal length of 3.5 m and can resolve objects on the ground as small as 36 cm; it can easily measure the size of an aircraft's air intake. What is the effective...