Question 1:

A)

Given:
$d = 400 \, \text{m}$
$t = 20 \, \text{s}$
Formula:
$v = \frac{d}{t}$
Calculation:
$v = \frac{400}{20} = 20 \, \text{m/s}$

B)

Given:
$d = 1500 \, \text{m}$
$t = 4 \times 60 = 240 \, \text{s}$
Formula:
$v = \frac{d}{t}$
Calculation:
$v = \frac{1500}{240} = 6.25 \, \text{m/s}$

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Question 2:

Given:
$u = 4 \, \text{m/s}$
$a = 2 \, \text{m/s}^2$
Formula:
$v = u + at$

A)

$t = 1 \, \text{s}$
$v = 4 + 2(1) = 6 \, \text{m/s}$

B)

$t = 5 \, \text{s}$
$v = 4 + 2(5) = 14 \, \text{m/s}$

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Related Questions:

1. What is the distance covered by the car in 30 seconds at the same speed?
2. How much time will the athlete take to cover 3 kilometers at the same speed?
3. What is the initial velocity of a particle if its final velocity after 3 seconds is 16 m/s, and acceleration is 2 m/s²?
4. How far does the particle travel in 5 seconds if starting from rest with uniform acceleration of 2 m/s²?
5. What is the average speed of a car that accelerates from 0 to 20 m/s in 10 seconds?

Tip:

To solve physics problems efficiently, always break them down into smaller steps by identifying the known values and selecting the right formula first.