The nichrome heating element in an electric drier operates on 240 V and generates thermal energy at the rate of 2.0 kW. The heating element shorts out and, in repairing it, the repairman shortens the nichrome wire by 10%
(Assume the temperature is unchanged. In reality, the resistivity of the wire will depend on its temperature.) What effect will the repair have on the power dissipated in the heating element? A) The power is still 2.0 kW.
B) The power increases to 2.2 kW.
C) The power decreases to 1.8 kW.
D) None of the given answers is correct.
B
You might also like to view...
The lifetime of a ?+ meson normally is 18 nanoseconds. In a large particle accelerator, scientists can create ?+ mesons moving at speeds close to the speed of light. What do the scientists observe when they measure the lifetime of a ?+ meson that is created at high speed?
A) The ?+ meson lasts much more than 18 nanoseconds. B) The ?+ meson lasts 18 nanoseconds. C) The ?+ meson lasts much less than 18 nanoseconds. D) The ?+ meson no longer decays and remains as a stable particle.
A conductor is placed in an electric field under electrostatic conditions. Which of the following statements is correct for this situation?
A) The electric field is zero inside the conductor. B) All valence electrons go to the surface of the conductor. C) The electric field on the surface of the conductor is perpendicular to the surface. D) All of the other answers apply.
Spectral lines for an element are often in the
A) infrared region. B) ultraviolet region. C) both of these D) neither of these
The wavelength of a ruby laser is 694.3 nm
What is the energy difference between the two energy states involved in laser action? (c = 2.9979 × 108 m/s, h = 6.626 × 10-34 J ? s, 1 eV = 1.6022 × 10-19 J) A) 1.537 eV B) 1.646 eV C) 1.786 eV D) 1.812 eV E) 3.572 eV