Exam 1: A: Foundations

A doubly charged ion (charge 2e)with velocity 6.9 × 10⁶ m/s moves in a circular path of diameter 60)0 cm in a magnetic field of 0.80 T in a mass spectrometer. What is the mass of this ion? (e = 1.60 × 10^-19C)

A light triangular plate OAB is in a horizontal plane.Three forces,F₁ = 6.0 N,F₂ = 9.0 N,and F₃ = 7.0 N,act on the plate,which is pivoted about a vertical axes through point O.In the figure, ₂ is perpendicular to OB.Consider the counterclockwise sense as positive.The sum of the torques about the vertical axis through point O,acting on the plate due to forces F₁,F₂,and F₃,is closest to

During a nuclear reaction,the particles involved lose 4.8 × 10^-28 kg of mass. How many joules of energy are released by this reaction? (c = 3.00 × 10⁸ m/s)

The components of vector are A_x = + 3.90 and A_y = -4.00.What is the angle measured counterclockwise from the +x-axis to vector ?

Four traveling waves are described by the following equations,where all quantities are measured in SI units and y represents the displacement. I: y = 0.12 cos(3x - 21t) II: y = 0.15 sin(6x + 42t) III: y = 0.13 cos(6x + 21t) IV: y = -0.27 sin(3x - 42t) Which of these waves have the same period?

As shown in the figure,a container has a vertical tube,whose inner radius is 32.00 mm,connected to it at its side.An unknown liquid reaches level A in the container and level B in the tube-level A being 5.0 cm higher than level B.The liquid supports a 20.0-cm high column of oil,between levels B and C,whose density is 460 kg/m³.What is the density of the unknown liquid?

Swimmers at a water park have a choice of two frictionless water slides as shown in the figure.Although both slides drop over the same height,h,slide 1 is straight while slide 2 is curved,dropping quickly at first and then leveling out.How does the speed v₁ of a swimmer reaching the end of slide 1 compares with v₂,the speed of a swimmer reaching the end of slide 2?

A very small round ball is located near a large solid sphere of uniform density.The force that the large sphere exerts on the ball

A billiard ball traveling at 3.00 m/s collides perfectly elastically with an identical billiard ball initially at rest on the level table. The initially moving billiard ball deflects 30.0° from its original direction. What is the speed of the initially stationary billiard ball after the collision?

A nonconducting sphere contains positive charge distributed uniformly throughout its volume.Which statements about the potential due to this sphere are true? All potentials are measured relative to infinity.(There may be more than one correct choice.)

The graph in the figure shows the electric field strength (not the field lines)as a function of distance from the center for a pair of concentric uniformly charged spheres.Which of the following situations could the graph plausibly represent? (There may be more than one correct choice.)

In order to lift a bucket of concrete,you must pull up harder on the bucket than it pulls down on you.

A wire along the z-axis carries a current of 6.8 A in the +z direction.Find the magnitude and direction of the force exerted on a 6.1-cm long length of the wire by a uniform magnetic field with magnitude 0.36 T in the -x direction.

A conducting sphere 45 cm in diameter carries an excess of charge,and no other charges are present.You measure the potential of the surface of this sphere and find it to be 14 kV relative to infinity. (k = 1/4πε₀ = 8.99 × 10⁹ N • m²/C²)The excess charge on this sphere is closest to

How fast must a nonrelativistic electron move so its de Broglie wavelength is the same as the wavelength of a 3.4-eV photon? (m_el = 9.11 × 10^-31 kg,c = 3.00 × 10⁸ m/s,1 eV = 1.60 × 10^-19 J)

For the wave shown in the figure,the frequency is

A very thin uniform rod,2.40 m long and of weight 135 N,has a frictionless hinge at its lower end.It starts out vertically from rest and falls,pivoting about the hinge.Just as it has rotated through an angle of 55.0°,what is the downward acceleration of the end farthest from the hinge?

Two objects,one of mass m and the other of mass 2m,are dropped from the top of a building.When they hit the ground

A 23 kg mass is connected to a nail on a frictionless table by a massless string 1.3 m long.There is no appreciable friction between the nail and the string.If the tension in the string is 51 N while the mass moves in a uniform circle on the table,how long does it take for the mass to make one complete revolution?

An object attached to an ideal massless spring is pulled across a frictionless surface.If the spring constant is 45 N/m and the spring is stretched by 0.88 m when the object is accelerating at 2.0 m/s²,what is the mass of the object?