Other Physics Answers

A wire with a resistance of 5Ω is drawn out through a die so that its new length is four times its original length. What is the resistance of the longer wire when the resistivity and density of the material are unchanged?

A human being can be electrocuted if a current as small as 50mA passes near the heart. An electrician with sweaty hands makes good contact with two conductors he is holding, one in each hand. If his resistance is 2kΩ, what is the fatal voltage?

1. A charged parallel plate with 15F connected to a battery with 9V. When a dielectric material was inserted between the parallel plates. What happens to the stored charges in the capacitor? 2. Find the capacitance of a layer of Al203 that is 0.5 m thick and 2000 mm2 of square area ( r= 8.854 x 10-12FM-1).

A constant net force of 350 N is applied to accelerate a cart in a frictionless surface from rest to a velocity of 65 m/s in 20 s. What is the mass of the cart?

A 60kg survivor of a shipwreck sits on a block of wood having volume of 1.6m³. Two birds of the block of the wood is under seawater (density = 1025 kg/m³ .find a the volume of diaplaced seawater by the block of wood, b. buoyant force on the block of wood and the survivor

a bicycle wheel turns with constant angular accceleration of 0.64 rad/s²:

a) how much time does it take to reach an angular velocity of 8 rad/sec starting from rest?

b) how many revolutions does the wheel turn in this time interval?

1/. A signal is transmitted from a ship and an echo is received from an object below the ship 4 s later. Calculate the distance of the object from the ship if the speed of sound in water is 1400 m/s.

The waves on a string have wave speed 8.00m/s, amplitude 0.0600m, and wavelength 0.400m. The waves travel in the -x direction and at t = 0s, the end of the string has its maximum upward displacement.

(a) Write a wave function describing the wave and

(b). Find the transverse displacement of a particle at x = 0.350m at time t = 0.150s

A sikorsky freight helicopter can easily lift a 5000 kg truck. If the acceleration of the truck is 1.5 m/s2 up, what is the net force being applied by the helicopter?