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2 years ago

Plz help I will mark as brainlest plz help me

Physics

1 answer:

Zielflug [23.3K]2 years ago

6 0

The kinematics can be found the distance between the cities is 22 km

Parameters

The instantaneous speed v = 90 km / h

Average speed v = 66 km / h ( $\frac{1000m}{1 km}$ ) ( $\frac{1 h}{3600 s}$ s) = 18.33 m / s

Time t = 20 min ( $\frac{60 s}{1 min}$ ) = 1200 s

To find

Distance

Kinematics studies the movement of bodies and establishes relationships between the position, velocity and acceleration of bodies.

Velocity is defined by the relationship between position and time in an interval

$v = \frac{\Delta x}{\Delta t}$

in the case of a large time interval the speed is called average, if the time interval becomes very small the speed is called instantaneous.

In this, the truck has some maximum speed points, but throughout the time interval its average speed is 66 km / h, so we can use the average speed ratio to calculate the distance between the cities.

$v = \frac{\Delta x}{\Delta t}$

Δx = v Δt

Δx = 18.33 1200

Δx = 2.2 10⁴ m

Let's reduce this distance to km

Δx = 2 10⁴ m ( $\frac{ 1 lm}{1000 m}$ )

Δx = 22 km

In conclusion using kinematics we can find the distance between the cities is 22 km

Learn more about average speed here:

brainly.com/question/17661499

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