Ramesh runs at the speed of 234 kmph. How many metres does he run in ten minutes?
39000 m
The question asks us to find the distance Ramesh runs in metres, given his speed in kilometres per hour (kmph) and the time in minutes. To solve this, we need to ensure all units are consistent. The speed is given in km/h, and the time is in minutes, but we need the distance in metres. Therefore, we must convert the given speed and time into units that will result in distance in metres.
To find the distance in metres, it's easiest to convert the speed from kilometres per hour (km/h) to metres per second (m/s) and the time from minutes to seconds. Alternatively, we could convert speed to metres per minute, but m/s is a standard conversion.
We know that:
So, to convert speed from km/h to m/s, we can use the conversion factor:
$\text{Speed (m/s)} = \text{Speed (km/h)} \times \frac{1000 \, \text{m}}{3600 \, \text{s}}$
This simplifies to:
$\text{Speed (m/s)} = \text{Speed (km/h)} \times \frac{5}{18}$
Let's apply this to Ramesh's speed:
Speed = 234 km/h
Speed in m/s = $234 \times \frac{5}{18}$
We can simplify the calculation:
Speed in m/s = $\left(\frac{234}{18}\right) \times 5$
$234 \div 18 = 13$
Speed in m/s = $13 \times 5 = 65$ m/s
So, Ramesh runs at a speed of 65 metres per second.
We are given the time in minutes:
Time = 10 minutes
We know that:
So, to convert time from minutes to seconds:
Time in seconds = Time in minutes $\times$ 60
Time in seconds = $10 \times 60 = 600$ seconds
So, Ramesh runs for 600 seconds.
The relationship between distance, speed, and time is given by the formula:
$\text{Distance} = \text{Speed} \times \text{Time}$
Now we have the speed in m/s and the time in seconds, which are consistent units:
Let's calculate the distance:
Distance = $65 \, \text{m/s} \times 600 \, \text{s}$
Distance = $65 \times 600$ metres
Distance = $39000$ metres
Ramesh runs 39000 metres in ten minutes.
| Quantity | Given Value | Converted Value (consistent units) |
|---|---|---|
| Speed | 234 kmph | 65 m/s |
| Time | 10 minutes | 600 seconds |
| Distance | ? | 39000 metres |
| Concept | Formula | Common Units | Conversion Tips |
|---|---|---|---|
| Speed | $\text{Speed} = \frac{\text{Distance}}{\text{Time}}$ | km/h, m/s, miles/h | km/h to m/s: Multiply by $\frac{5}{18}$ m/s to km/h: Multiply by $\frac{18}{5}$ |
| Distance | $\text{Distance} = \text{Speed} \times \text{Time}$ | km, metres, miles | Ensure speed and time units are compatible (e.g., m/s and seconds, km/h and hours) |
| Time | $\text{Time} = \frac{\text{Distance}}{\text{Speed}}$ | Hours, minutes, seconds | 1 hour = 60 minutes 1 minute = 60 seconds 1 hour = 3600 seconds |
In physics and mathematics problems involving quantities like speed, distance, and time, it is crucial to ensure that the units are consistent before performing calculations. If speed is in kilometres per hour and time is in seconds, you cannot directly multiply them. You must convert one or both quantities so that their units align. For example, if you want the distance in metres, and speed is in m/s, your time must be in seconds. If speed is in km/h, and you want distance in km, your time must be in hours.
Common conversions:
Paying attention to units is a common source of errors in calculations, so always double-check your units before applying the formula.
Rishi travels 198 km at 66 km/hr, the next 584 km at 73 km/hr and the next 656 km at 82 km/hr. What is his average speed (in km/hr) for the whole journey? (Round off your answer to two decimal places)