Explanation

Resolution improves with decreasing wavelength of light.

To observe a microparticle accurately, short-wavelength light (like blue or UV) gives the greatest precision.

Explanation

The SI unit of magnetic flux is Weber (Wb)

The Weber is commonly expressed in Volt-seconds

And a flux density of one Wb/m2 (one Weber per square meter) is one Tesla (T)

Explanation

According to Stokes' law, drag force 𝐹𝑑=6πηrv.

Hence, drag force is directly proportional to radius r of the sphere.

Explanation

A rocket expels gases backward, and by Newton’s 3rd law, it gains forward thrust.

This works on the principle of conservation of momentum.

Explanation

Radiation transfers energy without any medium, unlike conduction or convection.

Sun’s energy reaches satellites in space through electromagnetic waves (radiation).

Explanation

Step 1: Interpret the problem
The car moves in 3 phases:

1. Average speed = $20\text{ m/s}$ for $2.0\text{ s}$

2. Average speed = $40\text{ m/s}$ for $2.0\text{ s}$

3. Average speed = $60\text{ m/s}$ for $6.0\text{ s}$

We want the overall average speed = total distance / total time.

Step 2: Calculate distances in each phase
Using $\text{distance}=\text{average speed}\times \text{time}$:

• Phase 1: $20\times 2.0=40\text{ m}$

• Phase 2: $40\times 2.0=80\text{ m}$

• Phase 3: $60\times 6.0=360\text{ m}$

Total distance $=40+80+360=480\text{ m}$

Step 3: Total time
$2.0+2.0+6.0=10.0\text{ s}$

Step 4: Overall average speed

$${\mathrm{<b><font\; color="\#0000ff">v</font></b>}}_{\text{<b><font color="\#0000ff">avg</font></b>}}<b><font\; color="\#0000ff">=</font></b>\frac{\mathrm{<b><font\; color="\#0000ff">480</font></b>}}{\mathrm{<b><font\; color="\#0000ff">10</font></b>}}<b><font\; color="\#0000ff">=</font></b>\mathrm{<b><font\; color="\#0000ff">48</font></b>}\text{<b><font color="\#0000ff"> m/s</font></b>}$$

Explanation

Each slit diffracts the light, and these diffracted waves interfere with each other.

Thus, the observed fringe pattern is due to interference + diffraction together.

Explanation

At constant volume, no work is done, so heat supplied increases the internal energy.

This rise in internal energy appears as an increase in temperature.

Explanation

The student’s values (1.65, 1.72, 1.89) are close to each other → shows precision.

But they differ from the true value (2.35) → means not accurate.

Explanation

We apply Boyle’s Law:

P1​V1​ = P2​V2​
760×500 = P2​×300
P2 ​= 500×760 = 300​ = 1266.67torr