Which will have more resistance: 220V, 100W bulb or a 220V, 60W bulb?
Answers
The power dissipated by something with voltage across it is
(voltage)² / (resistance) .
You can see that resistance is in the denominator of the fraction, so larger resistances dissipate less power, and smaller resistances dissipate more power.
Here's an easy way to remember it: -- Connecting a piece of rubber (high resistance) across the terminals of a battery uses very little power from the battery. -- Laying a piece of wire (low resistance) across the terminals of a battery may draw so much power from the battery that the wire melts.
Since the voltage across both bulbs is expected to be the same, the bulb designed to dissipate 60 watts has higher resistance than the one designed to dissipate 100 watts.
Two waves with amplitudes of 75 units and 74 units arrive at a point in a medium simultaneously. If the two waves are out of phase with each other, what is the resultant amplitude of the wave?a. 74 units
b. 1 unit
c. 75 units
d. m149 units
Answers
Answer;
1 unit
Explanation;
Interference of a wave is the property a wave that occurs when two waves travelling in the same medium meet at a point or superpose at a point in the medium.
Interference may be constructive or destructive. Constructive occurs when two identical waves travelling in the same medium in phase meet at a point. The resulting wave has twice the amplitude of the individual waves.
Destructive interference occurs when two waves travelling in the same medium meet and out of phase. The resulting amplitude will be zero if the initial waves are identical, or the difference between the amplitude of the original waves if they are not identical.
Therefore; If the two waves one with an amplitude 75 units and the other 74 units, are out of phase with each other, the resultant amplitude of the resulting wave will be 1 unit, the difference between the amplitude of the original waves.
If the two waves have the SAME FREQUENCY and are exactly out of phase (180° apart), then the resultant wave will have the same frequency and an amplitude of 1 unit.
If the two waves do not have the SAME FREQUENCY, then their relative phase is meaningless.
Which statement best describes the equation caco3 2hcl → cacl2 co2 h2o?
Answers
it is balanced so the coefficient would be 1 and it seems to be dehydration synthesis?
To figure if this equation is balanced or not, we must determine if the reactants are the same as the products.
Ca=1 Ca=1 C=1 C=1 O=3 O=2+1=3 H=2 H=2 Cl=2 Cl=2
Since the amount of each element on the reactants side is equivalent to what is on the products side, we have a balanced equation.
Final answer: This equation is balanced.
Which of the following distances is the longest?a. 0.006 kilometersb. 0.3 decimeters
c. 820 meters
d. 20,000 millimeters
Answers
820 meters is the longest
Why does cold water have less thermal energy than hot water?
Answers
This is because the water molecules have less kinetic energy.
The device which disconnects the start winding in some split-phase motor circuits after a preset speed is obtained is thea. thermostat. b. commutator. c. brush spring. d. relay.