Physics Answers

3. If light is passed through a double-slit opening onto a screen, the pattern produced on the screen is ___________

A. a bright central band of light with slightly-diminished alternating bright and dark bands called nodes and antinodes.

B. a bright contral band of light with tiny lines toward the edges of the screen

C. a large circle of light with tiny circles around it.

D. equally-sized concentric circles of light

4. Light passes through a double-slit, producing bright and dark hands on a screen The dark hands are caused by waves from each slit _________

A. interfening constructively

B. meeting exactly one wavelength out of phase

C. meeting exactly one half wavelength out of phase.

D. meeting exactly one fourth wavelength out of phase.

5. Light of wavelength 580 nm is incident on a sit of width 0.300 mm: An observing Streen is placed 2.00m from the slit. Find the position of the first order dark frings from the center of the screen.

A. 0.26 mm

B. 1.9 mm

C. 3.9 mm

D. 7.7 mm

A grand father clock ticks each time the pendulum passes through the lowest point .if the pendulum is modeled as a simple pendulum .hiw long must it be for the ticks to occur once a second?

1. Two light sources are said to be coherent if they ___________

A. are of the same frequency.

B. are of the same frequency, and maintain a constant phase difference.

C. are of the same amplitude, and maintain a constant phase difference.

D. are of the same frequency and amplitude.

2. Coherent electromagnetic waves are not emitted by

A. two antennas connected to the same radio transmitter

B. two pinholes in an opaque shield over a sodium-vapor lamp

C. a pinhole in an opaque shield over a sodium-vapor lamp and its reflection in a mirror

D. two lasers

I need to know how to figure out how fast an object will fall when the weight of the object is known and falling distance of the object is known in inches per second. For example the distance is 8 feet and the weight of the object is 20 pounds. I also need to know what the speed will the object will have reached at the bottom of the 8 foot drop.

Determine the force of gravitational attraction between the earth (5.98 x1024

kg) and a 100 kg football player, when he is at a distance of 6.38 x 106 m from

earth’s center.

A 9 V battery is connected to a resistor with resistance of 1.60 Ω. (a) How many electrons leave the battery per minute? (b) If the resistor is made of copper wire with radius of 25 µm, calculate the length of the copper wire. The resistivity of copper is given as 1.68×10−8 Ω·m.

An empty swimming pool with a square floor dimension has a volume of 3y 2 m3 . Given the weight of air in the swimming pool is about 500 N and the air density is 1.29 kg/m3 . (a) Find the length of the swimming pool’s floor, y. (b) Determine the force exerted by air on the floor of the swimming pool

A 12N object is attached vertically by a string to a frictionless car that runs along a level track. The car with mass (m) kg covers a distance of 1.25m in 5s after it starts from rest. a)Find the final speed of the car. b)Find the loss in potential energy of 12 N object in falling through distance of 1.25m c) Gain in kinetic energy of the car and the hanging object. d)Mass of the car

A grocery is pulled along a rough horizontal surface of 6.0 N. It moves through a distance of 7.0 m at a constant speed. a)How much work is carried out by this force? b)How much work is carried out by friction? c)Find the total work done on the cart?

two possible angle to hit a target by a martyr shell fired with initial velocity of 98 metre per second are 15 degree and 75 degree calculate the range of projectile and the minimum time to required to hit the target