Answer:
Option B
Explanation:
Magnification of Microscope is

Mo= Magnification of objective lens and
Me= magnification of the eyepiece.
Both magnifications( of objective and eyepiece) are inversely proportional to the focal length.
Magnification,

when the focal length is less magnification will be high and when the magnification is the low focal length of the microscope will be more.
Thus. Magnification will increase by decreasing the focal length.
The correct answer is Option B i.e. using shorter focal length
Answer:
Momentum, p = 5 kg-m/s
Explanation:
The magnitude of the momentum of an object is the product of its mass m and speed v i.e.
p = m v
Mass, m = 3 kg
Velocity, v = 1.5 m/s
So, momentum of this object is given by :

p = 4.5 kg-m/s
or
p = 5 kg-m/s
So, the magnitude of momentum is 5 kg-m/s. Hence, this is the required solution.
Answer:
1.8 m/s
Explanation:
here's the solution : -
momentum = mass × velocity
=》18 × 0.1
=》1.8 m/s
Given E=2050 N/C
charge of an electron = 1.6×10^-19 C
USING E = F/Q , electric field = force ÷ charge
2050 = F ÷ (1.6×10^-19)....
make F subject of formula and get the answer