Physics Electrostatics Level: Misc Level
Two pont charges lie on the x axis. A charge of +9.9 uC is at the origin, and a charge of -5.1 uC is at x=10.0 cm. (a) At what position x would a third charge q3 be in equilibrium.(b) Does your answer to part (a) depend on whether q3 is positive or negative, explain,
Physics Electrostatics Level: Misc Level
When adhesive tape is pulled from a dispenser, the detached tape acquires a positive charge and the reaming tape in the dispenser acquires a negative charge.If the tape pulled from the dispenser has .14 uC of charge per centimeter, what length of tape must be be pulled to transfer 1.8x10 to the 13 th pwr electrons to the reaming tape
Physics Electrostatics Level: Misc Level
The electric potential of a system as a function of position along the axis is given in figure 20-22.(a) In which of the regions,12,3,or 4 do you expect E sub x to be greatest. In which region does E sub x have its greatest magnitude. Explain .(b) calculate the value of E sub x in each of the three regions 1,2,3, and 4.
Physics Electrostatics Level: Misc Level
The earth has an electric field with a magnitude of approximatly 100v/m near its surface.What is the potential difference between a point on the ground and a point on the same level as the top of the Washington Monument (555 ft high).
Physics Work,Power & Energy Level: Misc Level
A. 0.025 kg bullet is fired straight up at a falling wooden block that has a mass of 3.0 kg. The bullet has a speed of 740 m/s when it strikes the block. The block originally was dropped from rest from the top of a building and had been falling for a time t when the collision with the bullet occured. As a result of the collision, the block (with the bullet in it) reverses direction, rises, and comes to a momentary halt at the top of the building. Find the time t.
Physics Force & Laws Of Motion Level: Misc Level
When jumping straight down, you can be seriously injuredif you land stiff-legged. One way to avoid injury is to bend your knees upon landing to reduce the force of the impact.A 75 kg man just before contact with the ground has a speed of 6.8 m/s.
a) In a stiff- legged landing he comes to a halt in 1.8 ms. Find the average net force that acts on him during this time.
b)When he bends his knees, he comes to a halt in 0.14 s.Find the average force now.
c)During the landing, the force of the ground on the man points upward, while the force due to gravity points downward.The average net force acting on the man includes both of these force. Taking into account the directions of these forces, find the force of the ground on the man in parts (a) and (b).
Physics Work,Power & Energy Level: Misc Level
Consider the two moving boxcars in Example 5.Car1 has a mass of m1=65 x103 kg and moves at a velocity of v01=+0.85 m/s. Car 2, with a mass of m2=92 x103 kg and a velocity of v02=+1.4 m/s, overtakes car 1 and couples to it.Neglect the effects of friction in your answer.
a) Determine the velocity of their center of mass before the collision
b)Determine the velocity of their center of mass after the collision
c) Should your answer in part (b) be less than, greater than , or equal to the common velocity vf of the two coupled cars after the collion?Explain.
Physics Work,Power & Energy Level: Misc Level
The drawing shows a collison between two pucks on an air-hockey table.Puck A has a mass of 0.032 kg and is moving along the x axis with a velocity of +5.5 m/s.It makes a collision with puck B, which has a mass of 0.052 kg and is initially at rest. The collision is not head-on.After the collision, the two pucks fly apart with the angles shown in the drawing.
a) Find the final speed of puck A.
b) Find the final speed of puck B.
Physics Work,Power & Energy Level: Misc Level
A 2.50 g bullet, traveling at a speed of 420 m/s, strikes the wooden block of a ballistic pendulum, as shown. The block has a mass of 265 g.
a) Find the speed of the bullet/block combination immediately after the collision.
b) How high does the combination rise above its initial position?
Physics Work,Power & Energy Level: Misc Level
The lead female character in the movie Diamonds Are Forever is standing at the edge of an offshore oil rig. As she fires a gun, she is driven back over the edge and into the sea. Suppose the mass of a bullet is 0.009 kg, and its velocity is +712 m/s. Her mass (including the gun) is 45 kg.
a) What recoil velocity does she acquire in response to a single shot from a stationary position, assuming that no external force keeps her in place?
b) Under the same assumption,what would be her recoil velocity if, instead, she shoots a blank cartridge that ejects a mass of 5.0x 10-4 kg at a velocity of +712 m/s?
Physics Work,Power & Energy Level: Misc Level
A 55 kg swimmer is standing on a stationary 230 kg floating raft. The swimmer then runs off the raft horizontally with a velocity of +5.2 m/s relative to the shore.Find the recoil velocity that the raft would have if there were no friction and resistance due to the water.
Physics Force & Laws Of Motion Level: Misc Level
A stream of water strikes a stationary turbine blade horizontally, as the drawing illustrates. The incident water stream has a velocity of +18.0 m/s, while the exiting water stream has a velocity of -18.0 m/s. The mass of water per second that strikes the blade is 19.0 kg/s. Find the magnitude of the average force exerted on the water by the blade.
Physics Force & Laws Of Motion Level: Misc Level
A 2.9 kg rectangular air mattress is 2.46 m long, 0.511 m wide, and 0.172 m thick. What mass can it support in water before sinking? Answer in units of kg.
Physics Force & Laws Of Motion Level: Misc Level
Find the pressure exerted on the floor when the bed rests in its normal position. Assume that the entire lower surface of the bed makes contact with the floor.Answer in units of Pa.
Physics Force & Laws Of Motion Level: Misc Level
A water bed is 3.47 m on each vertical side and 31.9 cm high.The acceleration of gravity is 9.8 m/s^2. The density of water is 1000 kg/m3. Find its weight.Answer in units of N.
