Question

Some consumer groups urge pregnant women not to use electric blankets, in case there is a...

Some consumer groups urge pregnant women not to use electric blankets, in case there is a health risk from the magnetic fields from the current in the heater wires

a) Estimate the magnetic field strength a fetus might experience due to the current in a wire in the blanket that runs at 18 V and produces a power of 70 W, typical numbers.

b) What percentage of the earth’s magnetic field is this?

c) It’s now common to reduce the magnetic field near an electric blanket by combining wires in pairs that carry currents in opposite directions. How does this reduce the magnitude of the field?

Science   Physics   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

(a)

r~0.01m

(b)

Typical Earth's magnetic field: 25 micro Tesla

About 960% of the Earth's magnetic field.

(c)

The opposite direction currents produce magnetic field such that it cancels the magnetic field produced by electric blanket.(directions are opposite)

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
You are in New Zealand in the winter and it is cold. You decide to buy...
You are in New Zealand in the winter and it is cold. You decide to buy an electric blanket and notice that there is a safety notice that says “if pregnant you shouldn’t use this due to possible health risk to the baby from magnetic fields.” The wire carries a 1A current. a) Estimate, and give your reasoning behind your estimate, the magnetic field strength the baby experiences inside the womb, and how does this value compare to the Earth’s...
1. The strength of an electromagnet can be increased by A. Decreasing the number of coils...
1. The strength of an electromagnet can be increased by A. Decreasing the number of coils of wire B.Adding a core of iron to the coil of wire C.Decreasing the current in the wire D.All of these 2. Auroras are caused by A.the van Allen Radiation belts trapping harmful charged particles from space in the Earth’s magnetic field and producing dancing lights. B.Disturbances in the Earth’s magnetic field, near the poles, which allow charged particles from space to dip into...
A magnetic field, strength 3T, has a direction out of the page. A loop of wire...
A magnetic field, strength 3T, has a direction out of the page. A loop of wire sits in the field and on the plane of the page (area vector of loop is out of page). The loop is much smaller than the extent of the field. The magnetic field starts to slowly change at a rate of -0.0001T/s. Looking down on the loop, which statement is correct? A. Magnetic flux out of page decreasing; anti-clockwise current induced in loop B....
If two wires carry current next to each other, they will exert a force on each...
If two wires carry current next to each other, they will exert a force on each other. The force is caused by magnetic fields. One current creates a magnetic field, and this field exerts a force on the other current. The magnitude of the field created by a long, straight current-carrying wire is given by Equation 1 below; B= (μ0i)/(2πr) where i is the current and r is the distance from the wire. The magnitude of the force exerted on...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT