DariaV

This page lists questions and answers that were posted by visitors named DariaV.

Questions

The following questions were asked by visitors named DariaV.

Physical therapists know as you soak tired muscles in a hot tub, the water will cool down as you heat up. If a 68.1 person at 37.1 oC immerses in 50.2 kg of water at 40.5o C, the equilibrium temperature is 38.7 oC. What is the specific heat of the person?...

If you put a balloon in a warm oven and assume the balloon cannot pop. Will the the balloon continue expanding forever or will it eventually stop expanding?

1/2 = α Delta T what is this?

Calculate the change in temperature that would shrink a room-temperature balloon to one-half its size. Vo is 10 Vf is 5

A hydraulic device is used to lift the bucket of a backhoe. The input is a round cylinder that is 1.0 cm in radius. The output piston is round and 6.0 cm in radius. How much can it lift if the input force is 500 newtons? so converting radius to Area A=Pi...

A steel rod is 2.55 cm long at 16 o C in an operating room. It is placed in a patient's leg where it rises to 37 o C. What will the change in length be? coefficient of linear expansion for steel 13.0 x10^-6 I am getting .0006915 but the answer is .000643...

The volume of air in a balloon is 4.5 liters when inflated. External pressure decreases the volume to 1.1 liters. If the original pressure was 1.00 atmosphere, what pressure would be required to produce that change if everything else is constant? 4.1 atm...

A fireman's water hose has a diameter of about 4.0 inches. The water is flowing through it at about 14.0 m/s. The nozzle's diameter drops to about 0.80 inches. If there is no friction, what would the exit velocity of the water be?

There are 40 ml of air in a large syringe. With the exit hole plugged, you squeeze the air down to about 10 ml. If the original pressure was 1.0 atmosphere, how much pressure do you need to exert to squeeze it down to 10 ml in atmospheres?

A hydraulic jack has an input piston that is 1.2 cm2 in area and an output piston that is 144 cm2 in area. How much input or effort force in newtons is needed to lift a car that weighs 25,000 newtons?

Two equal charges repel one another with a force of 4.0 x 10-4 N when they are 10 cm apart. If they are moved until the separation is 20 cm, the repulsive force will be??

An i Pod draws about 3.7 volts (i Pod batteries are rated for 3.7 volts and 1200 mAhours.) Ignore the internal resistance of the battery. If the i Pod has a resistance of 12 ohms, what is the current through the i Pod?

Three different size lights are running off a low voltage system. The resistance of the three lights are R1 =3 ohms, R2 = 9 ohms, and R3 = 9 ohms. They are all connected in parallel with a 5.0 V battery. The internal resistance of the battery is negligibl...

A light bulb with a resistance of 3.0 ohms has a voltage difference of 6.0 V across its leads. What is the current through the bulb?

When needed, use 340 m/s for the speed of sound and 3.00 x 108 m/s for the speed of light. A hiker determines the length of a lake by listening for the echo of her shout reflected by a cliff at the far end of the lake. She hears the echo 2.20 s after shou...

A wave on a rope has 6 nodes, including one at each end. If the wave train or system of waves is 5 meters long, what is the wavelength?

A sound wave has a length of 0.66 meters. If the frequency of the wave is 512 Hz (high C), what is the wave velocity?

A standing wave on a string has a velocity of 42 m/s and a period of 0.01 s. What is the frequency of the wave?

While studying for this quiz you realize that you still have 100 g of lukewarm coffee at 40°C left in a paper cup. When you pour 50 g of boiling water into the cup, the temperature of the resulting coffee-like mixture will now be??

A boat floating in a large pool and displaces 25 liters of water. What is the buoyant force on the boat. 1000 liters = 1 m3 Density of water = 1000 kg/m3

The potential difference across the terminals of a storage battery not connected in any circuit is observed to be 12 V. When it is connected to an external resistance the potential difference across the terminals is observed to be 11 V while the current i...

If the speed of sound is 1100 feet per second and a tuning fork oscillates at 440 cycles per second, what is the wavelength of the sound produced?

Answers

The following answers were posted by visitors named DariaV.

When the pressure inside the balloon is equal to pressure outside the balloon. I'm not sure the other reason.

room temp is 20 C right?

sorry this : α what does that symbol mean?

so using Charles' law

my book says that is what the expansion coefficient is for steel

I got it 350 m/s

I=R/V 1.67A? Right?

so the answer is 2m? 5/6 =.83?