Exam 1: A: Foundations

An ac source of period T and maximum voltage V is connected to a single unknown ideal element that is either a resistor,and inductor,or a capacitor.At time t = 0 the voltage is zero.At time t = T/4 the current in the unknown element is equal to zero,and at time t = T/2 the current is I = -I_max,where I_max is the current amplitude.What is the unknown element?

An aircraft performs a maneuver called an "aileron roll." During this maneuver,the plane turns like a screw as it maintains a straight flight path,which sets the wings in circular motion.If it takes it 35 s to complete the circle and the wingspan of the plane is 11 m,what is the acceleration of the wing tip?

Approximately how many times does an average human heart beat in a lifetime?

Fluid fills the container shown in the figure.At which of the indicated points is the pressure greatest?

A ball is projected upward at time t = 0.0 s,from a point on a roof 90 m above the ground.The ball rises,then falls and strikes the ground.The initial velocity of the ball is 36.2 m/s if air resistance is negligible.The time when the ball strikes the ground is closest to

If the electric potential at a point in space is zero,then the electric field at that point must also be zero.

A pair of charged conducting plates produces a uniform field of 12,000 N/C,directed to the right,between the plates.The separation of the plates is 40 mm.An electron is projected from plate A,directly toward plate B,with an initial velocity of v₀ = 1.0 × 10⁷ m/s,as shown in the figure.(e = 1.60 × 10^-19 C, Ε₀ = 8.85 × 10^-12 C²/N • m²,m_el = 9.11 × 10^-31 kg)The distance of closest approach of the electron to plate B is nearest to

A bag of potato chips contains 2.00 L of air when it is sealed at sea level at a pressure of 1.00 atm and a temperature of 20.0°C. What will be the volume of the air in the bag if you take it with you,still sealed,to the mountains where the temperature is 7.00°C and atmospheric pressure is 70.0 kPa? Assume that the bag behaves like a balloon and that the air in the bag is in thermal equilibrium with the outside air. (1 atm = 1.01 × 10⁵ Pa)

In the figure,a constant external force P = 160 N is applied to a 20.0-kg box,which is on a rough horizontal surface.While the force pushes the box a distance of 8.00 m,the speed changes from 0.500 m/s to 2.60 m/s.The work done by friction during this process is closest to

The cross section of a long coaxial cable is shown in the figure,with radii as given.The linear charge density on the inner conductor is -30 nC/m and the linear charge density on the outer conductor is -70 nC/m. The inner and outer cylindrical surfaces are respectively denoted by A,B,C,and D,as shown.(ε₀ = 8.85 × 10^-12 C²/N • m²) The radial component of the electric field at a point that 34 mm from the axis is closest to

Assume that a certain city consumes electrical energy at an average rate of 2.0 × 10⁹ W.What would be the mass change in producing enough energy to keep this city running for 21 weeks? (c = 3.00 × 10⁸ m/s)

A pair of narrow slits,separated by 1.8 mm,is illuminated by a monochromatic light source.Light waves arrive at the two slits in phase,and a fringe pattern is observed on a screen 4.8 m from the slits.If there are 5.0 complete bright fringes per centimeter on the screen near the center of the pattern,what is the wavelength of the monochromatic light?

If two vectors point in opposite directions,their cross product must be zero.

An electron moves with a speed of 8.0 × 10⁶ m/s along the +x-axis. It enters a region where there is a magnetic field of 2.5 T,directed at an angle of 60° to the +x-axis and lying in the xy-plane. (1 eV = 1.60 × 10^-19 C,m_el = 9.11 × 10^-31 kg)Calculate the magnitude of (a)the magnetic force on the electron. (b)the acceleration of the electron.

If all the components of a vector are equal to 1,then that vector is a unit vector.

Two sources of light illuminate a double slit simultaneously.One has wavelength 570 nm and the second has an unknown wavelength.The m = 5 bright fringe of the unknown wavelength overlaps the M = 4 bright fringe of the light of 570 nm wavelength.What is the unknown wavelength?

A 5.00-kg box slides 4.00 m across the floor before coming to rest. What is the coefficient of kinetic friction between the floor and the box if the box had an initial speed of 3.00 m/s?

An object is placed 100 cm in front of a diverging lens with a focal length of magnitude 25 cm.A converging lens having a focal length of magnitude 33.33 cm is placed 30 cm past the first lens.Where is the final image formed?

A puddle of water has a thin film of gasoline floating on it.A beam of light is shining perpendicular on the film.If the wavelength of light incident on the film is 560 nm and the indices of refraction of gasoline and water are 1.40 and 1.33,respectively,what is the minimum thickness of the film to see a bright reflection?

In the figure,a proton is projected horizontally midway between two parallel plates that are separated by 0.50 cm.The electrical field due to the plates has magnitude 610,000 N/C between the plates away from the edges.If the plates are 5.60 cm long,find the minimum speed of the proton if it just misses the lower plate as it emerges from the field.(e = 1.60 × 10^-19 C,ε₀ = 8.85 × 10^-12 C²/N • m², m_el = 9.11 × 10^-31 kg)