1
NEET 2019
+4
-1
A hollow metal sphere of radius R is uniformly charged. The electric field due to the sphere at a distance r from the centre :
A
zero as r increases for r < R, decreases as r increases for r > R
B
zero as r increases for r < R, increases as r increases for r > R.
C
decreases as r increases for r < R and for r > R.
D
increases as r increases for r < R and for r > R.
2
NEET 2019
+4
-1
Two point charges A and B, having charges +Q and – Q respectively, are placed at certain distance apart and force acting between them is F. If 25% charge of A is transferred to B, then force between the charges becomes :
A
F
B
$${{16F} \over 9}$$
C
$${{9F} \over {16}}$$
D
$${{4F} \over 3}$$
3
NEET 2019
+4
-1
Two parallel infinite line charges with linear charge densities +$$\lambda$$ C/m and -$$\lambda$$ C/m are placed at a distance of 2R in free space. What is the electric field mid-way between the two line charges?
A
$${{2\lambda } \over {\pi {\varepsilon _0}R}}$$ N/C
B
zero
C
$${\lambda \over {\pi {\varepsilon _0}R}}$$ N/C
D
$${\lambda \over {2\pi {\varepsilon _0}R}}$$ N/C
4
NEET 2018
+4
-1
An electron falls from rest through a vertical distance h in a uniform and vertically upward directed electric field E. The direction of electric field is now reversed, keeping its magnitude the same. A proton is allowed to fall from rest in it through the same vertical distance h. The time of fall of the electron, in comparison to the time of fall of the proton is
A
smaller
B
5 times greater
C
10 times greater
D
equal
EXAM MAP
Medical
NEET