1. A car starts from rest and accelerates at a constant rate to 80km/h in 6s in positive direction. What is the acceleration?
2. After how long will the car speed be 120km/h if it keep accelerating at the same rate as in 1.?
3.After the car reached speed of 120km/h it travels at constant velocity for next 100. What distance does it cover in that 100s?
1. 80 km/h = 22.22 m/s
Divide that by 6s for the acceleration
a = 3.70 m/s^2
2. If the speed reaches 80 km/h in 6 s and the acceleration stays the same, it will reach 120 km/h in 1.5 x 6 = 9 seconds.
3. 120 km/h = 33.33 m/s
Multiply that by 100s for the answer, in meters.
Or, you can multiply 120 km/h by 100/3600 hours, for the distance in km.
To answer these questions, you'll need to understand some basic physics equations. Let's break it down step by step:
1. The first question asks for the acceleration of the car. We can use the formula:
acceleration = (final velocity - initial velocity) / time
Given:
- Initial velocity = 0 km/h (since the car starts from rest)
- Final velocity = 80 km/h
- Time = 6 seconds
Plugging these values into the formula, we get:
acceleration = (80 km/h - 0 km/h) / 6 s
acceleration = 80 km/h / 6 s
acceleration = 13.33 km/h/s
Therefore, the acceleration of the car is 13.33 km/h/s.
2. The second question asks for the time it takes for the car to reach a speed of 120 km/h, given that it continues to accelerate at the same rate as in question 1.
We know the acceleration is still 13.33 km/h/s. Let's denote the time it takes for the car to reach 120 km/h as 't'.
Using the formula for final velocity, given constant acceleration:
final velocity = initial velocity + (acceleration * time)
Given:
- Initial velocity = 0 km/h (since the car starts from rest)
- Final velocity = 120 km/h
- Acceleration = 13.33 km/h/s
Plugging these values into the formula, we get:
120 km/h = 0 km/h + (13.33 km/h/s * t)
120 km/h = 13.33 km/h/s * t
Now we can solve for 't':
t = 120 km/h / 13.33 km/h/s
t = 9 seconds
Therefore, it will take 9 seconds for the car to reach a speed of 120 km/h.
3. The third question asks for the distance the car covers in 100 seconds while it maintains a constant velocity of 120 km/h.
Since the car is moving at a constant velocity, its acceleration is zero. The formula to calculate distance traveled with constant velocity is:
distance = velocity * time
Given:
- Velocity = 120 km/h
- Time = 100 seconds
Plugging these values into the formula, we get:
distance = 120 km/h * 100 s
distance = 12000 km
Therefore, the car covers a distance of 12000 km in 100 seconds while traveling at a constant velocity of 120 km/h.