Physics Motion and Time Part 11 (Questions 2) Class 7 VII

TL;DR

Calculate the distance between Salma's house and school using speed and time, and analyze distance-time graphs for different situations.

Transcript

hello friends this video on motion and time part 11 is brought to you by example.com no more fear from exam question number six salma takes 15 minutes from her house to reach her school on a bicycle if the bicycle has a speed of 2 meter per second calculate the distance between her house and the school so let's say this is her house and this is her... Read More

Key Insights

• 🤒 Salma's distance from her house to school is 1.8 kilometers, which she covers in 15 minutes on a bicycle with a speed of 2 meters per second.
• 🫥 In a distance-time graph, a straight line represents uniform motion, while a horizontal line represents no motion.
• 🐎 The correct relation for speed is speed = distance / time, with the SI unit for speed being meter per second.
• 🐎 The total distance covered by a car with different speeds can be calculated by adding the distances traveled during each speed period.

Questions & Answers

Q: How can we calculate the distance between Salma's house and her school?

The distance can be calculated by multiplying the speed (2 meters per second) by the time taken (900 seconds), resulting in a distance of 1.8 kilometers.

Q: What does a distance-time graph look like for a car moving with a constant speed?

A distance-time graph for a car moving with a constant speed would be a straight line, indicating that it covers equal distances in equal intervals of time.

Q: What is the correct relation for speed?

The correct relation for speed is speed = distance / time, where speed is measured in distance per unit time.

Q: What is the basic unit of speed?

The basic unit of speed is meter per second, as speed is distance per unit time, and the SI unit for distance is meter and for time is second.

Q: How do we calculate the total distance covered by a car with changing speeds over time?

We calculate the distance for each speed period (40 km/h for 15 minutes and 60km/h for the next 50 minutes), which is 10 kilometers and 15 kilometers, respectively. The sum of these distances is the total distance covered, which is 25 kilometers.

Q: Which vehicle is moving faster based on the distance-time graph?

By comparing the slopes of the distance-time graph of vehicles A and B, we can determine the speed. If the slope of one vehicle is steeper (A in this case), it means it is moving faster.

Summary & Key Takeaways

• Salma takes 15 minutes to travel from her house to school on a bicycle with a speed of 2 meters per second, resulting in a distance of 1.8 kilometers.

• The distance-time graph for a car moving with a constant speed would be a straight line, while for a parked car, the distance would remain constant over time.

• The correct relation for speed is speed = distance / time, where speed is measured in distance per unit time.

• The basic unit of speed is meter per second.

• Given the speed of a car (40 km/h for 15 minutes and 60 km/h for the next 50 minutes), the total distance covered by the car is 25 kilometers.

• The steeper the slope of a distance-time graph, the greater the speed of the vehicle.