# TechnoBoi11

Popular questions and responses by TechnoBoi11-
## Physics/Math

Two vectors are given by a = 3.3i + 6.5j, and b = 2.5i + 4.9j. Find a) a·b = b) (a + b)·b = c) the component of a in the direction of b = a) (3.3x2.5) + (6.6x4.9) = b) (5.8x2.5) + (11.4x4.9)= c) (a·b)/(magnitude of b)= Great! I got it :)

*asked on March 1, 2007* -
## Physics/Math

A can of sardines is made to move along an x axis from x1 = 0.2 m to x2 = 1.2 m by a force given by F = iF0exp(-0.4x), with x in meters and F0 = 4.5 N. (Here exp is the exponential function.) How much work is done on the can by the force? For Further

*asked on March 3, 2007* -
## Physics/Math

A cold package of hot dogs slides rightward across a frictionless floor through a distance d = 20.5 cm while three forces are applied to it. Two of the forces are horizontal and have the magnitudes F1 = 5.00 N and F2 = 1.00 N; the third force is angled

*asked on March 1, 2007* -
## Physics/Math

For the vectors a = (3.9 m)i + (4.8 m)j, and b = (5.4 m)i - (2.0 m)j, give the x and y components, magnitudes, and directions of the following vector operations. (a.) a + b ______(x component) ______(y component) ______(magnitude) ______° (direction from

*asked on January 27, 2007* -
## Physics/Math

A 1.50 kg snowball is fired from a cliff 13.5 m high with an initial velocity of 14.0 m/s, directed 41.0° above the horizontal. (a) Using energy techniques, rather than techniques of Chapter 4, find the speed of the snowball as it reaches the ground below

*asked on March 11, 2007* -
## Physics

A thin rod, of length L and negligible mass, that can pivot about one end to rotate in a vertical circle. A heavy ball of mass m is attached to the other end. The rod is pulled aside through an angle and released. What is the speed of the ball at the

*asked on March 9, 2007* -
## Physics

Zero, a hypothetical planet, has a mass of 1.0x10^23 kg, a radius of 3.0x10^6 m, and no atmosphere. A 10 kg space probe is to be launched vertically from its surface. (a) If the probe is launched with an initial kinetic energy of 5.0x10^7 J, what will be

*asked on March 9, 2007* -
## Physics/Math

A thin rod, of length L and negligible mass, that can pivot about one end to rotate in a vertical circle. A heavy ball of mass m is attached to the other end. The rod is pulled aside through an angle and released. (a)What is the speed of the ball at the

*asked on March 7, 2007* -
## Physics/Math

You drop a 1.8 kg textbook to a friend who stands on the ground 9 m below the textbook with outstretched hands 1.50 m above the ground. (a) What is the speed of the textbook when it reaches the hands? m/s (b) If we substituted a second textbook with twice

*asked on March 7, 2007* -
## Physics/Math

A 2.8 kg body is at rest on a frictionless horizontal air track when a horizontal force F acting in the positive direction of an x axis along the track is applied to the body. The force F is applied to the body at t = 0, and the graph records the position

*asked on March 5, 2007* -
## Physics/Science #2

A rock is thrown verticaly upward from ground level at time t = 0. At t = 1.65 s it passes the top of a tall tower, and 0.95 s later it reaches its maximum height. What is the height of the tower? height = _______ m First, find the initial velocity from

*asked on January 25, 2007* -
## Physics/Math

Ok...I figured out part a but I am having trouble with b. part a was: Zero, a hypothetical planet, has a mass of 1.0x10^23 kg, a radius of 3.0x10^6 m, and no atmosphere. A 10 kg space probe is to be launched vertically from its surface. (a) If the probe is

*asked on March 14, 2007* -
## Physics/Math

Ok...I figured out part a but I am having trouble with b. part a was: Zero, a hypothetical planet, has a mass of 1.0x10^23 kg, a radius of 3.0x10^6 m, and no atmosphere. A 10 kg space probe is to be launched vertically from its surface. (a) If the probe is

*asked on March 12, 2007* -
## Physics

Zero, a hypothetical planet, has a mass of 1.0 1023 kg, a radius of 3.0 106 m, and no atmosphere. A 10 kg space probe is to be launched vertically from its surface. (a) If the probe is launched with an initial kinetic energy of 5.0 107 J, what will be its

*asked on March 9, 2007* -
## Re: Physics/Math

Posted by Technoboi11 on Wednesday, March 7, 2007 at 1:09am. Zero, a hypothetical planet, has a mass of 1.0x10^23 kg, a radius of 3.0x10^6 m, and no atmosphere. A 10 kg space probe is to be launched vertically from its surface. (a) If the probe is launched

*asked on March 9, 2007* -
## Physics/Math

Zero, a hypothetical planet, has a mass of 1.0 1023 kg, a radius of 3.0 106 m, and no atmosphere. A 10 kg space probe is to be launched vertically from its surface. (a) If the probe is launched with an initial kinetic energy of 5.0 107 J, what will be its

*asked on March 7, 2007* -
## Physics/Math

A 1.50 kg snowball is fired from a cliff 12.5 m high with an initial velocity of 14.0 m/s, directed 41.0° above the horizontal. (a) Using energy techniques, rather than techniques of Chapter 4, find the speed of the snowball as it reaches the ground below

*asked on March 7, 2007* -
## Physics/Math

A machine carries a 5.0 kg package from an initial position of di = (0.50 m) i + (0.75 m) j + (0.20 m) k at t = 0 to a final position of df = (8.00 m) i + (11.0 m) j + (7.40 m) k at t = 13 s. The constant force applied by the machine on the package is F =

*asked on March 5, 2007* -
## Physics/Math

At a certain instant, a particle-like object is acted on by a force F = (3.0 N) i - (1.0 N) j + (8.0 N) k while the object's velocity is v = - (2.0 m/s) i + (4.0 m/s) k. What is the instantaneous rate at which the force does work on the object? (b) At some

*asked on March 5, 2007* -
## Physics/Math

An iceboat is at rest on a frictionless frozen lake when a sudden wind exerts a constant force of 212 N, toward east, on the boat. due to the angle of the sail, the wind causes the boat to slide in a straight line for a distance of 7.0 m in a direction

*asked on March 5, 2007* -
## Physics/Math

A single force acts on a 5.0 kg particle-like object in such a way that the position of the object as a function of time is given by x = 3.0t - 4.0t 2 + 1.0t 3, with x in meters and t in seconds. Find the work done on the object by the force from t = 0 to

*asked on March 3, 2007* -
## Physics/Math

What work is done by a force (in newtons) F = 3.1xi + 3.1j, with x in meters, that moves a particle from a position r1 = 2.1i + 2.5j to r2 = - -4.9i -3.9j? For Further Reading * Physics/Math - bobpursley, Thursday, March 1, 2007 at 6:27am Work is the dot

*asked on March 3, 2007* -
## Re: Physics/Math

What work is done by a force (in newtons) F = 3.1xi + 3.1j, with x in meters, that moves a particle from a position r1 = 2.1i + 2.5j to r2 = - -4.9i -3.9j? For Further Reading * Physics/Math - bobpursley, Thursday, March 1, 2007 at 6:27am Work is the dot

*asked on March 2, 2007* -
## Re: Physics/Math

A single force acts on a 5.0 kg particle-like object in such a way that the position of the object as a function of time is given by x = 3.0t - 4.0t 2 + 1.0t 3, with x in meters and t in seconds. Find the work done on the object by the force from t = 0 to

*asked on March 2, 2007* -
## Re: Physics/Math

A can of sardines is made to move along an x axis from x1 = 0.2 m to x2 = 1.2 m by a force given by F = iF0exp(-0.4x), with x in meters and F0 = 4.5 N. (Here exp is the exponential function.) How much work is done on the can by the force? For Further

*asked on March 2, 2007* -
## Physics/Math

What work is done by a force (in newtons) F = 3.1xi + 3.1j, with x in meters, that moves a particle from a position r1 = 2.1i + 2.5j to r2 = - -4.9i -3.9j? Work is the dot product of Force and displacement. Change in displacement is r2 minus r1. I will be

*asked on March 1, 2007* -
## Physics/Math

A single force acts on a 5.0 kg particle-like object in such a way that the position of the object as a function of time is given by x = 3.0t - 4.0t 2 + 1.0t 3, with x in meters and t in seconds. Find the work done on the object by the force from t = 0 to

*asked on March 1, 2007* -
## Physics/Math

A can of sardines is made to move along an x axis from x1 = 0.2 m to x2 = 1.2 m by a force given by F = iF0exp(-0.4x), with x in meters and F0 = 4.5 N. (Here exp is the exponential function.) How much work is done on the can by the force? Work is the

*asked on March 1, 2007* -
## Physics/Math

A force F = (4.0 N)i + cj acts on a particle as the particle goes through displacement d = (3.4 m)i - (2.0 m)j. (Other forces also act on the particle.) What is the value of c if the work done on the particle by force F is each of the following? (a) zero

*asked on March 1, 2007* -
## PHYSICS

When a particle moves on a circle at constant speed, its acceleration vector: a) is zero m/s^2 b) points toward the center of the circle. c) points parallel to its velocity vector. It's zero m/s^2 since it's moving at a constant speed, right? No. Remember,

*asked on February 18, 2007* -
## Decaf Coffee

Is decaf coffee completely decaffinated?? .. or are there low amounts of caffiene in brewed decaf coffee? (i'm researching about people with health conditions concerning caffiene... if they even should be drinking decaf coffee at all!!) - can anyone find

*asked on February 14, 2007* -
## Physics

An electron's position is given by r = 4.00t i - 6.00t2 j + 5.00 k, with t in seconds and r in meters. (a) In unit-vector notation, what is the electron's velocity v(t)? (Answer in terms of i, j, k, and t.) ___ m/s (b) What is v in unit-vector notation at

*asked on February 1, 2007* -
## Physics - Projectile Motion

A ball rolls horizontally off the edge of a tabletop that is 1.60 m high. It strikes the floor at a point 1.58 m horizontally away from the table edge. (Neglect air resistance.) (a) How long was the ball in the air? ___ s (b) What was its speed at the

*asked on February 1, 2007* -
## Physics/Math

In the vector sum A + B = C , vector A has a magnitude of 13.1 m and is angled 49° counterclockwise from the +x direction, and vector C has a magnitude of 15.0 m and is angled 20.0° counterclockwise from the -x direction. What are (a) the magnitude and

*asked on January 27, 2007* -
## physics - converting radians to degrees

i know how to convert degrees to radians.. ie: 40* x (2pi rad/360*) = 0.70 rad .. i cant figure out how to do the opposite.. can anyone show me how? thanks! ~lor .70 rad (360 deg/2PI rad )= 40o radians = degrees*2*pi/360 = 0.69813 degrees = rad*360/2*pi

*asked on January 27, 2007* -
## Physics/Math

A displacement vector r in the xy plane is 6 m long and directed at angle [Theta] = 36°. Determine the x and y components of the vector. _____ m (x component) _____ m (y component) I will be happy to check your answers, or critique your thinking. We don't

*asked on January 27, 2007* -
## Physics/Math

What is the sum of the following four vectors in unit-vector notation? For that sum, what are (b) the magnitude, (c) the angle in degrees, and (d) the angle in radians? E: 6.36 m at +0.90 rad F: 4.52 m at -75 ° G: 3.31 m at +1.20 rad H: 5.4 m at -210 °

*asked on January 27, 2007* -
## Physics/Math

In the vector sum A + B = C , vector A has a magnitude of 13.1 m and is angled 49° counterclockwise from the +x direction, and vector C has a magnitude of 15.0 m and is angled 20.0° counterclockwise from the -x direction. What are (a) the magnitude and

*asked on January 27, 2007* -
## Physics/Science #3

A ball is thrown vertically downward from the top of a 35.9-m tall building. The ball then passes the top of a window that is 10.7 m above the ground 2.00 s after being thrown. What is the speed of the ball as it passes the top of the window? The equation

*asked on January 25, 2007* -
## Physics/Science

A startled armadillo leaps upward rising 0.547 m in the first 0.202 s. (a) What is its initial speed as it leaves the ground? _____m/s (b) What is its speed at the height of 0.547 m? _____m/s (c) How much higher does it go? _____m Use distance vs time:

*asked on January 25, 2007*