Lv 2472 points

# shane

• ### How do you solve this physics problem?

An ideal spring of negligible mass is 12.00 cm long when nothing is attached to it. When you hang a 3.15-kg weight from it, you measure its length to be 13.40 cm. If you wanted to store 10.0 J of potential energy in this spring, what would be its total length? Assume that it continues to obey Hooke's law.

• ### How do you solve this elastic potential energy physics problem?

An ideal spring of negligible mass is 12.00 cm long when nothing is attached to it. When you hang a 3.15-kg weight from it, you measure its length to be 13.40 cm. If you wanted to store 10.0 J of potential energy in this spring, what would be its total length? Assume that it continues to obey Hooke's law.

My text book says the answer is "21.52cm or 2.48cm"- I'm assuming the 2nd one is supposed to be in meters.

I've been working on it for about an hour, but I keep getting a different answer than that of my textbook.

• ### (projectile motion) How do I solve this physics problem?

A cannon, located 60.0 m from the base of a vertical 25.0-m-tall cliff, shoots a 15-kg shell at 43.0 degrees above the horizontal toward the cliff. What must the minimum muzzle velocity be for the shell to clear the top of the cliff?

the back of the book says the answer is 32.6 m/s

• ### How do I solve this physics problem?

A 1000-kg car is pulling a 300-kg trailer. Together, the car and trailer have an acceleration of 2.15m/s^2 in the forward direction. Neglecting frictional forces on the trailer, determine the resultant force exerted by the car on the road.

The answer for this problem is in the back of my text book. It reads: 1.02*10^4 N at 74.1 below horizontal and rearward.

• ### Application of Newton's Laws Physics problem?

A 5.0-kg bucket of water is raised from a well by a rope. If the upward acceleration of the bucket is 3.0m/s^2, find the force exerted by the rope on the bucket.

My book says the answer is 64 N. How is this done?

• ### Vectors....The answer is 249ft upstream. How do you do this physics problem.?

A rowboat crosses a river with a velocity of 3.30 mi/h at an angle 62.5 degrees north of west relative to the water. The river is 0.505mi wide and carries an eastward current of 1.25mi/h. How far upstream is the boat when it reaches the opposite shore?

• ### The answer is 615. How do you do this physics problem?

A boat moves through the water of a river at 10 m/s relative to the water, regardless of the boats direction. If the water in the river is flowing at 1.5 m/s, how long does it take the boat to make a round trip consisting of a 300-m displacement downstream followed by a 300-m displacement upstream?

• ### Can you help me with this physics problem?

A rowboat crosses a river with a velocity of 3.30 mi/h at an angle 62.5 degrees north of west relative to the water. The river is 0.505mi wide and carries an eastward current of 1.25mi/h. How far upstream is the boat when it reaches the opposite shore?

• ### Vectors and Two-Dimensional Motion problem. The answer is 7.5- Can you show me how to do it?

A quarterback throws a football toward a receiver with an initial speed of 20 m/s at an angle of 30 degrees above the horizontal. At that instant the receiver is 20 m from the quarterback. In what direction and with what constant speed should the receiver run in order to catch the football at the level at which it was thrown?

The answer is 7.5 m/s in the direction the ball was thrown. How do I solve this?

• ### Can you find two vectors with different lengths that have a vector sum of zero?

What restrictions are required for three vectors to have a vector sum of zero?

Can you find a vector quantity that has magnitude of zero but components that are different from zero?

Can the magnitude of a vector be less than the magnitude of any of its components?

• ### Which direction will the reaction proceed? Do I need to use an ICE table?

I started with 1atm of PCl5. After equilibrium is achieved, the new pressure is fifty percent higher than the starting pressure; (PCl5, PCl3, Cl2 mixture has a total pressure of 1.5atm).

PCl5(g)<--->PCl3(g) + Cl2(g)

What is the equilibrium constant (Kp) of the reaction?

If I were to combine 1atm of each of the 3 gases into a flask, what will happen to the pressure in the flask? In what direction will the reaction move?

• ### Can you help me solve this differential equation?

Find the value of k for which the constant function x(t)=k is a solution of the differential equation 7 t^3 (dx)/(dt) -9 x + 5 = 0 .

• ### calculus application to physics and engineering problem?

A bucket is created by rotating the curve y=sqrt(x-1) around the y axis, for y values from y=0 to y=5. How do you set up an integral to find the work required to pump water out of this bucket if it was full of water?

• ### How do you set up an integral to find the volume of this three dimensional object?

The object has a base in the shape of an isosceles right triangle with legs of length 4, and parallel cross sections perpendicular to the base and parallel to a leg of the triangle have the shape of a semicircle.

• ### How do you solve this hydrostatic force problem using calculus?

A dam is built so that the wall facing the water is shaped like the region above the curve y=0.7 x^2 and below the line y= 200 . (Here, distances are measured in meters.) The water level is 30 meters below the top of the dam. Find the force (in Newtons) exerted on the dam by water pressure. (Water has a density of 1000 "kg"/m^3, and the acceleration of gravity is 9.8 m/sec^2 .)

How do you solve this problem?

It would also be greatly appreciated if you can give me the answer as well. I know the answer- points to whoever answers correctly.

• ### Using your knowledge of electron configurations can you help me explain the following observations?

Why does silver tend to form ions with a charge of 1+, but the elements to the left and right of silver in the periodic table tend to form ions with 2+ charges?

Why does the heavier group 13 elements (Ga, In, Ti) tend to form ions with charges of 1+ or 3+ but not 2+?

Why does the heavier elements of group 14 (Sn, Pb) and group 4 (Ti,Zr,Hf) tend to form ions with charges of 2+ or 4+?

• ### finding zeros...am i supposed to multiply both sides by x^2?

f(x)=2x-(1185408/x^2)

what are the values of x where f(x) is equal to zero?

• ### optimization calculus problem..... A'(x)=0 when x=___?

problem:

A box with a square base and open top must have a volume of 296352 cm^3. What are the dimensions of the box that minimize the amount of material used?

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work I have done:

V=x^2h=296352

h=296352

surface area=A(x)= x^2+4x(296352/x^2)=x^2+(1185408/x)

A'(x)=2x-(1185408/x^2)

When does A'(x)=0?

A''(x)=__?