Question

A TMS (transcranial magnetic stimulation) device creates very rapidly changing magnetic fields. The field near a typical pulsed-field machine rises from 0 T to 2.5 T in 200 ?s. Suppose a technician holds his hand near the device so that the axis of his 1.8-cm-diameter wedding band is parallel to the field.

What emf is induced in the ring as the field changes?

If the band is made of a gold alloy with resistivity 6.2×10?8??m and has a cross-section area 4.3 mm2 , what is the induced current?

Answer #1

**here,**

**change in magnetic feild , dB = 2.5 T**

**timne , t = 2 * 10^-4 s**

**diamter , d = 0.018 m**

**radius , r = 0.009 m**

**the emf induced , EMF = area * dB/dt**

**EMF = pi * 0.009^2 * 2.5 /( 2 * 10^-4)**

**EMF = 3.18 V**

**b)**

**resistivity , p = 6.2 * 10^-8 ohm.m**

**area , a = 4.3 * 10^-6 m^2**

**length ,l = 2 * pi * r**

**l = 2 * pi * 0.009**

**l = 0.05652 m**

**resistance , R = p * l /a**

**R = 6.2 * 10^-8 * 0.05652 /( 4.3 * 10^-6)**

**R = 8.14 * 10^-4 ohm**

current , I = EMF /R

I = 3.90 * 10^3 A

the current induced is 3.90* 10^3 A

A TMS (transcranial magnetic stimulation) device creates very
rapidly changing magnetic fields. The field near a typical
pulsed-field machine rises from 0 T to 2.5 T in 200 μs. Suppose a
technician holds his hand near the device so that the axis of his
2.3-cm-diameter wedding band is parallel to the field.
Part A- What emf is induced in the ring as the field changes?
Express your answer with the appropriate units.
Part B- If the band is made of...

Transcranial magnetic stimulation (TMS) is a noninvasive
technique used to stimulate regions of the human brain (see
figure). In TMS, a small coil is placed on the scalp and a brief
burst of current in the coil produces a rapidly changing magnetic
field inside the brain. The induced emf can stimulate neuronal
activity.
(a) One such device generates an upward magnetic field within
the brain that rises from zero to 1.50 T in 140 ms. Determine the
induced emf around...

MY NOTES
Transcranial magnetic stimulation (TMS) is a noninvasive
technique used to stimulate regions of the human brain (see
figure). In TMS, a small coil is placed on the scalp and a brief
burst of current in the coil produces a rapidly changing magnetic
field inside the brain. The induced emf can stimulate neuronal
activity.
(a) One such device generates an upward magnetic field within
the brain that rises from zero to 1.50 T in 135 ms. Determine the
induced...

1. An MRI technician moves his hand from a region of very low
magnetic field strength into an MRI scanner’s 2.00 T field with his
fingers pointing in the direction of the field.
Find the average emf induced in his wedding ring in mV, given
its diameter is 2.05 cm and assuming it takes 0.325 s to move it
into the field.
2. An emf is induced by rotating a 1000 turn, 25 cm diameter
coil in the Earth’s 5.00...

An MRI technician moves his hand from a region of very low
magnetic field strength into an MRI scanner's 1.80 T field with his
fingers pointing in the direction of the field. His wedding ring
has a diameter of 2.21 cm, and it takes 0.360 s to move it into the
field.
(a) What average current is induced in the ring if its
resistance is 0.0100 Ω? (Enter the magnitude in amperes.)
________ A
(b) What average power is dissipated...

An MRI technician moves his hand from a region of very low
magnetic field strength into an MRI scanner's 1.70 T field with his
fingers pointing in the direction of the field. His wedding ring
has a diameter of 2.23 cm, and it takes 0.370 s to move it into the
field.
a.) What average current is induced in the ring if its
resistance is 0.0100 ?? (Enter the magnitude in amperes.)
b.) What average power is dissipated (in Watts)?...

An MRI technician moves his hand from a region of very low
magnetic field strength into an MRI scanner's 1.50 T field with his
fingers pointing in the direction of the field. His wedding ring
has a diameter of 2.27 cm, and it takes 0.380 s to move it into the
field.
(a)What average current is induced in the ring if its resistance
is 0.0100 Ω? (Enter the magnitude in amperes.)
(b)What average power is dissipated (in W)?
(c) What...

An MRI technician moves his hand from a region of very low
magnetic field strength into an MRI scanner's 1.80 T field with his
fingers pointing in the direction of the field. His wedding ring
has a diameter of 2.29 cm, and it takes 0.330 s to move it into the
field.
a) What average current is induced in the ring if its resistance
is 0.0100 Ω? (Enter the magnitude in amperes.)
b) What average power is dissipated (in W)?...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 19 minutes ago

asked 37 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago