Exam 1: A: Foundations

A 360-nm thick oil film floats on the surface of the water.The indices of refraction of the oil and the water are 1.5 and 1.33,respectively.The surface of the oil is illuminated from above at normal incidence with white light.What TWO wavelengths of light in the 400-nm to 800-nm wavelength band are most strongly reflected?

An unusual spring has a restoring force of magnitude F = (2.00 N/m)x + (1.00 N/m²)x²,where x is the stretch of the spring from its equilibrium length.A 3.00-kg object is attached to this spring and released from rest after stretching the spring 1.50 m. If the object slides over a frictionless horizontal surface,how fast is it moving when the spring returns to its equilibrium length?

It is a well-known fact that water has a higher specific heat than iron.Now,consider equal masses of water and iron that are initially in thermal equilibrium.The same amount of heat,30 calories,is added to each one.Which statement is true?

A 6.1-kg solid sphere,made of metal whose density is 2600 kg/m³,is suspended by a cord.When the sphere is immersed in a liquid of unknown density,the tension in the cord is 26 N.Find the density of the liquid.

In the circuit shown in the figure,an ideal ohmmeter is connected across ab with the switch S open.All the connecting leads have negligible resistance.The reading of the ohmmeter will be closest to

In the figure,the inner loop carries a clockwise current I that is increasing.The resistor R is in the outer loop and both loops are in the same plane.The induced current through the resistor R is

An astronaut is standing on the surface of a planetary satellite that has a radius of 1.74 × 10⁶ m and a mass of 7.35 × 10²² kg.An experiment is planned where a projectile needs to be launched straight up from the surface.What must be the minimum initial speed of the projectile so it will reach a height of 2.55 × 10⁶ m above this satellite's surface? (G = 6.67 × 10^-11 N • m²/kg²)

If a force always acts perpendicular to an object's direction of motion,that force cannot change the object's kinetic energy.

A figure skater rotating at 5.00 rad/s with arms extended has a moment of inertia of 2.25 kg • m². If the arms are pulled in so the moment of inertia decreases to 1.80 kg • m²,what is the final angular speed?

A rocket is moving at 1/4 the speed of light relative to Earth.At the center of this rocket,a light suddenly flashes.To an observer at rest on Earth

Suppose that you wish to construct a simple ac generator having an output of 12 V maximum when rotated at 60 Hz. A uniform magnetic field of 0.050 T is available. If the area of the rotating coil is 100 cm²,how many turns do you need?

An object is moving forward with a constant velocity.Which statement about this object MUST be true?

The figure shows two forces,each of magnitude 4.6 N,acting on an object.The angle between these forces is 40°,and they make equal angles above and below the horizontal.What third force will cause the object to be in equilibrium (acceleration equals zero)?

A 120-V rms voltage at 60.0 Hz is applied across an inductor,a capacitor,and a resistor in series.If the peak current in this circuit is 0.8484 A,what is the impedance of this circuit?

When you blow some air above the upper face of a paper strip,the paper rises.This occurs because

Which one of the phasor diagrams shown below best represents a series LRC circuit driven at resonance?

If the magnitude of the cross product of two vectors is one-half the dot product of the same vectors,what is the angle between the two vectors?

A certain electric furnace consumes 24 kW when it is connected to a 240-V line. What is the resistance of the furnace?

Which of the following is an accurate statement?

A factory robot drops a 10 kg computer onto a conveyor belt running at 3.1 m/s.The materials are such that μ_s = 0.50 and μ_k = 0.30 between the belt and the computer.How far is the computer dragged before it is riding smoothly on the belt?