MCQ
An electron revolves $6 × 10^{15}$ times/sec in circular loop. The current in the loop is
- ✓$0.96\,mA$
- B$0.96 \,\mu A$
- C$28.8\, A$
- DNone of these
✓
Answer
Correct option: A.
$0.96\,mA$
a
(a)$i = 6 \times {10^{15}} \times 1.6 \times {10^{ - 19}} = 0.96\,mA{\rm{.}}$
(a)$i = 6 \times {10^{15}} \times 1.6 \times {10^{ - 19}} = 0.96\,mA{\rm{.}}$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
A pendulum $($ positively charged and hinged at some length above the plate$)$ is swinging above a parallel plate $($infinitely large and having negative charge$)$, now consider the following statements, $($consider gravity$):$
→Suppose a current carrying wire has a cross-sectional area that, gradually become smaller along the wire, has the shape of a very long cone as shown in figure. Choose the correct statement
If the ratio of intensities of two waves is 1 : 25, then the ratio of their amplitudes will be
Two like magnetic poles of strength $ 10$ and $40$ $ SI$ units are separated by a distance $30 \,cm$. The intensity of magnetic field is zero on the line joining them
→The focal lengths of the lenses of an astronomical telescope are $50\, cm$ and $5 \,cm.$ The length of the telescope when the image is formed at the least distance of distinct vision is
→The given circuit has two ideal diodes connected as shown in the figure below. The current flowing through the resistance $R _1$ will be
→To explain his theory, Bohr used
Match List I with List II and select the correct answer using the codes given below the lists :
Codes :
| List I (Position of the object) |
List II (Magnification) |
| (I) An object is placed at focus before a convex mirror | (A) Magnification is -∞ |
| (II) An object is placed at centre of curvature before a concave mirror | (B) Magnification is 0.5 |
| (III) An object is placed at focus before a concave mirror | (C) Magnification is +1 |
| (IV) An object is placed at centre of curvature before a convex mirror | (D) Magnification is -1 |
| (E) Magnification is 0.33 |
What is the dimension of the dipole moment?
Image formed by a concave mirror of focal length $6 \,cm$, is $3$ times of the object, then the distance of object from mirror is......$cm$
→