Physics Electromagnetic Induction Level: Misc Level
At a given instant the current and self-induced emf in an inductor are directed as indicated in Fig.32-26.The induced emf is 19 V and the rate of change of the current is 23 kA/s; find the inductance in henries. The dealine is 9 AM eastren time
Physics Electromagnetic Induction Level: Misc Level
A circular coil has a 8.74 cm radius and consists of 33.0 closely wound turns of wire.An externally produced magnetic field of magnitude 3.37 mT is perpendicular to the coil.(a) If no current is in the coil, what magnetic flux links its turns? (b)When the current in the coil is 4.69 A in a certain direction,the net flux through the coil is found to vanish. What is in henries the inductance of the coil?
Physics Force & Laws Of Motion Level: Misc Level
A man weighing 220 pounds stands on a scale in an elevator. when the elevator is stand still the scale shows 220.5 pounds.when the elevator starts the scale shows 240.5. which way is the elevator going, up ordown?what is the acceleration?
Physics Work,Power & Energy Level: Misc Level
A child on a sled slides down an incline with a 20 degree slope.the incline is 10 meters long.The coefficient of kinetic friction is 0.12.Using Newton,s method and energy methods; the mass of the child and sled is 25 kg
a) Find the force of friction
b)Find the acceleration down the hill
c)Find the work done by the friction force
d) Find the kinetic energy and velocity at the bottom of the hill.
Physics Force & Laws Of Motion Level: Misc Level
Scientists are experimenting with a kind of gun that may eventually be used to fire payloads directly into orbit. In one test, this gun accelerates a 5.0 kg projectile from rest to a speed of 4.5 x103 m/s.The net force accelerating the projectile is 5.5 x105N. How much time is required for the projectile to come up to speed?
Physics Force & Laws Of Motion Level: Misc Level
A 1720 kg car is traveling with a speed of 15.0 m/s.What is the magnitude of the horizontal net force that is required to bring the car to a halt in a distance of 56.0 m?
Physics Gravitation Level: Misc Level
The weight of an object is the same on two different planets. The mass of plane A is only twenty-five percent that of planet B. Find rA/rB, which is the ratio of the radii of the planets.
Physics Force & Laws Of Motion Level: Misc Level
A rock of mass 30 kg accidentally breaks loose from the edge of a cliff and falls straight down . The magnitude of the air resistance that opposes its downward motion is 270 N.What is the magnitude of the acceleration of the rock?
Physics Gravitation Level: Misc Level
A bowling ball(mass=7.2 kg, radius=0.11 m) and a billiard ball (mass=0.32 kg, radius=0.028 m) may each be treated as uniform spheres. What is the magnitude of the maximum gravitational force that each can exert on the other?
Physics Force & Laws Of Motion Level: Misc Level
Airplane flight recorders must be able to survive catastrophic crashes.Therefore, they are typically encased in crash-resistant steel or titanium boxes that are subjected to rigorous testing. one of the tests is an impact shock test, in which the box must survive being thrown at high speeds against a barrier.A 41 kg box is thrown at a speed of 245 m/s and is brought to a halt in a collision that lasts for a time of 5.2 ms. What is the magnitude of the average net force that acts on the box during coliion?
Physics Force & Laws Of Motion Level: Misc Level
A 410-kg sailboat has an acceleration of 0.43 m/s2 at an angle of 31% north of east. Find the magnitude and direction of the net force that acts on the sailboat.
Physics Force & Laws Of Motion Level: Misc Level
Two forces, F1 and F2, act on the 5.00 kg block shown in the drawing. The magnitudes of the force are F1=50.0 N and F2=31.0 N. What is the horizontal acceleration (magnitude and direction) of the block?
Physics Vectors Level: Misc Level
A force vector has a magnitude 630 N and a direction of 45% north of east. Determine the magnitude and direction of the components of the force that point along the north -south line and along the east-west line.
Physics Magnetism,Magnetic Effects Of Current Level: Misc Level
A loop is placed near a long straight wire.The loop carries a current of 2A and the wire carries a current of 10 A. The radius of the loop is 0.1 m.What distance s must the edge of the loop be from the wire such that the magnetic field at the center of the loop be zero?IN which direction (clockwise or counter) must the current in the loop be traveling?
Physics Magnetism,Magnetic Effects Of Current Level: Misc Level
Four long wires in the figure carry 2.5 A current in the directions indicated. Find the net force per unit length on the wire at the lower left. All sides are 15 cm in length
