KCET · Physics · Current Electricity
\(\mathrm{B}_{1}, \mathrm{~B}_{2}\) and \(\mathrm{B}_{3}\) are the three identical bulbs connected to a battery of steady emf with key \(\mathrm{K}\) closed. What happens to the brightness of the bulbs \(B_{1}\) and \(B_{2}\) when the key is opened?
- A Brightness of the bulb \(\mathrm{B}_{1}\) increases and that of \(\mathrm{B}_{2}\) decreases
- B Brightness of the bulbs \(\mathrm{B}_{1}\) and \(\mathrm{B}_{2}\) increase
- C Brightness of the bulb \(\mathrm{B}_{1}\) decreases and \(\mathrm{B}_{2}\) increases
- D Brightness of the bulbs \(\mathrm{B}_{1}\) and \(\mathrm{B}_{2}\) decrease
Answer & Solution
Correct Answer
(C) Brightness of the bulb \(\mathrm{B}_{1}\) decreases and \(\mathrm{B}_{2}\) increases
Step-by-step Solution
Detailed explanation
When key \(\mathrm{K}\) is opened, bulb \(\mathrm{B}_{2}\) will not draw any current from the source, so that terminal voltage of source increases. Hence, power consumed by bulb increases, so light of the bulb becomes more. The brightness of bulb \(\mathrm{B}_{1}\) decreases.
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Physics
- A step down transformer has \( 50 \) turns on secondary and \( 1000 \) turns on primary winding. If a
transformer is connected to \( 220 \mathrm{~V} 1 \mathrm{AA} \).C. source, what is output current of the transformer?KCET 2014 Easy - A sphere, a cube and a thin circular plate all of same material and same mass initially heated to same high temperature are allowed to cool down under similar conditions. Then, theKCET 2020 Medium
- A 30 cm long capillary tube is dipped in water, water rises upto a height of \(10\) cm due to capillarity. If this experiment is conducted in a freely falling water in an elevator, then the length of the water column becomesKCET 2026 Medium
- The ratio of hydraulic stress to the corresponding strain is known asKCET 2015 Easy
- Suppose the acceleration due to gravity at the earth's surface is \(g \text{ m/s}^2\) and at the surface of moon it is \(g' \text{ m/s}^2\). An M kg passenger goes from the earth to the moon in a spaceship moving with a constant velocity (Neglect all other objects in the sky). Which curve best represents the weight (net gravitational force) as a function of time?
KCET 2026 Hard - A force between two protons is same as the force between proton and neutron. The nature of the force isKCET 2014 Hard
More PYQs from KCET
- The appropriate reagent for the following transformation is
KCET 2018 Easy - If 30J energy is trapped at product level, then how much energy will be available to peacock as food in the following chain?
Plant → Mice → Snake → PeacockKCET 2015 Easy - In this diagram showing the L. S. of an embryo of grass identify the answer having the correct combination of alphabets with the right part.
KCET 2014 Hard - The point on the curve \( y^{2}=x \) where the tangent makes an angle of \( \pi / 4 \) with \( x \)-axis isKCET 2017 Easy
- A jet plane having a wing span of \( 25 \mathrm{~m} \) is travelling horizontally towards east with a speed of
\( 3600 \mathrm{~km} / \mathrm{h}^{-1} \).If the Earth's magnetic field at the location is \( 4 \times 10^{-4} \mathrm{~T} \) and the angle of dip is
\( 30^{\circ} \), then the potential difference between the ends of the wing isKCET 2018 Hard - If \(\mathbf{a}\) and \(\mathbf{b}\) are vectors such that \(|\mathbf{a}+\mathbf{b}|\) \(=\mid \mathbf{a}-\mathbf{b}\), then the angle between \(\mathbf{a}\) and \(\mathbf{b}\) isKCET 2007 Medium