MCQ
Artificial radioactivity was discovered by:
- AKlaproth.
- BRontgen.
- CIrene Curie and Joliot.
- DP. Curie and M. Curie.
✓
Answer
- Irene Curie and Joliot.
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Consider three converging lenses L1, L2 and L3 having identical geometrical construction. The index of refraction of L1 and L2 are $\mu_1$ and $\mu_2$ respectively. The upper half of the lens L3 has a refractive index $\mu_1$ and the lower half has $\mu_2$. A point object O is imaged at O1 by the lens L1 and at O2 by the lens L2 placed in same position. If L3 is placed at the same place:
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(a) 15 |
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$\frac{1}{\text{r}^3}$
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