Exam 1: A: Foundations

A piece of thin uniform wire of mass m and length 3b is bent into an equilateral triangle.Find the moment of inertia of the wire triangle about an axis perpendicular to the plane of the triangle and passing through one of its vertices.

The two rotating systems shown in the figure differ only in that the two identical movable masses are positioned at different distances from the axis of rotation.If you release the hanging blocks simultaneously from rest,and if the ropes do not slip,which block lands first?

What is the ratio of the escape speed of a rocket launched from sea level to the escape speed of one launched from Mt.Everest (an altitude of 8.85 km)? The radius of the earth is 6.38 × 10⁶ m.

If the magnitude of vector is less than the magnitude of vector ,then the x component of is less than the x component of .

What is the radius of a sphere that has a density of 5000 kg/m³ and a mass of 6.00 kg?

A ring with a clockwise current (as seen from above the ring)is situated with its center directly above another ring,which has a counter-clockwise current,as shown in the figure.In what direction is the net magnetic force exerted on the top ring?

Vector = -3.00 + 3)00 And vector = 3)00 + 4)00 ) What is vector = + ?

Two identical balls are thrown directly upward,ball A at speed v and ball B at speed 2v,and they feel no air resistance.Which statement about these balls is correct?

An ideal gas increases in temperature from 22°C to 42°C by two different processes.In one process,the temperature increases at constant volume,and in the other process the temperature increases at constant pressure.Which of the following statements about this gas are correct? (There may be more than one correct choice.)

The critical angle in air for a particular type of glass is 39.0°.What is the speed of light in this class glass? (c = 3.00 × 10⁸ m/s)

A Carnot refrigerator has a coefficient of performance of 2.5.The refrigerator consumes 50 W of power.How much heat is removed from the interior of the refrigerator in 1 hour?

In the figure,a C-shaped conductor is in a uniform magnetic field B,which is increasing.The polarity of the induced emf in terminals X and Y is

In an electromagnetic wave,the electric and magnetic fields are oriented such that they are

In a shuffleboard game,the puck slides a total of 12 m before coming to rest.If the coefficient of kinetic friction between the puck and the horizontal board is 0.28,what was the initial speed of the puck?

A beam of red light and a beam of violet light each deliver the same power on a surface.For which beam is the number of photons hitting the surface per second the greatest?

The angular magnification of a refracting telescope is 40 x.When the object and final image are both at infinity,the distance between the eyepiece and the objective is 143.5 cm.The telescope is used to view a distant radio tower.The real image of the tower,formed by the objective,is 6.0 mm in height.The focal point of the eyepiece is positioned at the real image.What is the focal length of the objective lens?

Equal but opposite charges Q are placed on the square plates of an air-filled parallel-plate capacitor.The plates are then pulled apart to twice their original separation,which is small compared to the dimensions of the plates.Which of the following statements about this capacitor are true? (There may be more than one correct choice.)

Two point charges Q₁ and Q₂ of equal magnitudes and opposite signs are positioned as shown in the figure.Which of the arrows best represents the net electric field at point P due to these two charges?

Electric charge is uniformly distributed inside a nonconducting sphere of radius 0.30 m.The electric field at a point P,which is 0.50 m from the center of the sphere,is 15,000 N/C and is directed radially outward.What is the maximum magnitude of the electric field due to this sphere?

A straight wire that is 0.60 m long is carrying a current of 2.0 A.It is placed in a uniform magnetic field of strength 0.30 T.If the wire experiences a force of 0.18 N,what angle does the wire make with respect to the magnetic field?