Physics Gravitation Level: Misc Level
A distan star has two planets following circular orbits about the star with one planet four times the distance from the star as the other planet. If the planet closer to the star has a period of 2 years, determine the period of the planet farther from the star *Need just solution*
Physics Force & Laws Of Motion Level: Misc Level
A hanging sign which weighs 50 N is pished out from the wall by a bracket, and supported by a rope tied to the wall.The rope makes an angle of 30 degrees with the wall. Find the force of tention in the rope.
Physics Vectors Level: Misc Level
An Airplne is flying towards a destination 320 km due east of its starting point. There is a wind of 50 km/h from the northwest (towards bearing 135). The pilot wishes to make the trip in 40 minutes.What should his airspeed vector be?(The diagram is essential)
Physics Vectors Level: Misc Level
Sarah rows a boat across a river that is flowing at a steady 3 km/h. She keeps the boat pointing straight across, maintaining a rowing speed of 5km/h. The river is 1 km wide.
(a) From a vector diagram, find the actual crossing speed and direction of Sarah,s boat.
(b) Find the time it takes to cross the river,
(c) Find the distance down river that Sarah reaches the shore.
Physics Vectors Level: Misc Level
A rock of a weight 200N is resting on an incline which makes an angle of 30 degrees to the horizontal. Find the component of the weight force that makes the rock inclined to slide down the incline.
Physics Vectors Level: Misc Level
Given the vectors A (10 N.) and B (8N.) at an angle of 143 degrees to each other. Find the vector A-B
Physics Vectors Level: Misc Level
Find the resultant of two forces, 5N.and 6N. at an angle of 20 degrees to each other.
Physics Magnetism,Magnetic Effects Of Current Level: Misc Level
A wire carries a current of 22 A from east to west. Assume that at this location the Earth,s magnetic field is horizontal and directerd from south to north. The magnitude of the field at this location is 500uT.Find the magnitude and dirction of the magnetic force on a 36-m length of wire in this field. How does the force change if the current runs from west to east?
Physics Electromagnetic Induction Level: Misc Level
A step-up transformer is designed to have an out put of 2200 V when the primary is connected across a 110-V source. If there are 80 turns in the primary, how many turns are required on the secondary?If a load resistor across the secondary draws a current of 1.5 A, what is the current in the primary?
Physics Electromagnetic Induction Level: Misc Level
A coil with 25 turns of wire is wound on a square frame 1.80 cm on a side. Each turn of wire has the same area, equal to that of the frame,and the total resistance of the coil is 0.35 ohms. A uniform magnetic field is applied perpendicular ot the plane of the coil. If the field changes uniformly from 0 to 0.500 T in 0.800 s, find the magnitude of the induced emf in the coil while the field is changeing.
Physics Magnetism,Magnetic Effects Of Current Level: Misc Level
A circular coil consists of 5 loops each of diameter 1.0m. The coil is placed in an extenal magnetic field of 0.5T.When the coil carries a current of 4.0 A, a torque of magnitude 3.93 N*m acts on it.Determine the angle between the normal to the plane of the coil and the direction of the magnetic field.
(a)0
(b)30
(c)45
(d)60
(e)90
Physics Alternating Current Level: Misc Level
A 220 ohm resistor is connected an ac voltage source V=(150V*sin [2 PI (60 Hz) t]. What is the average power delivered to this circuit?
(a) 51 W
(b)110 W
(c) 280 W
(d)320W
(e) 550 W
Physics Current Electricity Level: Misc Level
The current through a certain heater wire is found to be fairly independent of its temperature. If the current through the heater wire is doubled, the amount of energy delivered by the heater in a given time interval will
(a)increase by a factor of two<----my answer
(b) decrease by a factor of two
(c) increase by a factor of four
(d) decrease by a factor of four
(e) increase by a factor of eight
Physics Units Level: Misc Level
Which one of the following combinations of units is equivalent to the ohm?
(a) V/C
(b) A/J
(c) J/S
(d) J* s/C^2
(e) W/A,<------my answer
Physics Misc Topic Level: Misc Level
Which one of the following combinations of units is equivalent to the ohm?
(a) V/C
(b) A/J
(c) J/S
(d) J* s/C^2
(e) W/A,<------my answer
