Physics, 19.11.2019 21:31 dbhuggybearow6jng

Distinguish between instantaneous speed and average speed. a man drives a car a distance of 200km at an average speed of 44kmh¹,what must be it's average speed for the next 220km, if the car is to cover the total distance in 9 hours?

Answers: 2

Show answers

Answers

Answer from: kingtrent81

49.32km/h

Explanation:

Given a man drives a car a distance of 200km at an average speed of 44km/h

We know that $average speed=\frac{total distance}{time}$

initially $44=\frac{200}{time}$

time=4.54 hours

Now Given the total trip should be completed in 9 hours

the time taken to complete the second part of the trip is 9-4.54=4.46 hours

Given the distance travelled in the second half is 220km

We know that $average speed=\frac{total distance}{time}$

$average speed=\frac{220}{4.46}$

average speed = 49.32 km/h.

Answer from: Quest

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

$f\alpha \frac{dp}{dt}$

⇒ $f= k \frac{dp}{dt}$

here k is the proportionality constant whose value is 1.

$f=\frac{dp}{dt}$

$f= \frac{d[mv]}{dt}$

$f= m\frac{dv}{dt} +v\frac{dm}{dt}$

$f=ma+v\frac{dm}{dt}$ [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.

Answer from: Quest

Answerigneous bedrock of the oceanic crust;

Another question on Physics

Physics, 22.06.2019 07:00

The speed of sound in ice, water, and steam is shown. what best explains the speed of sound in different states of matter? sound travels fastest in ice because energy is easier to transfer when the molecules are close together. sound travels slowest in steam because the sound has to move around the gas molecules that are far apart. sound travels fastest in ice because the temperature of solids is always greater, so the heat transfers the sound energy. sound travels slowest in steam because the pressure is so great the sound cannot travel though the steam particles.

Answers: 1

Answer

Physics, 22.06.2019 11:00

A2.00-m long piano wire with a mass per unit length of 12.0 g/m is under a tension of 8.00 kn. what is the frequency of the fundamental mode of vibration of this wire?

Answers: 3

Answer

Physics, 22.06.2019 14:30

What conclusion can be made based on the temperature of soil when the light hits the soil at 0°, 45°, and 90° angles in section 2 of the experiment? did your results support your hypothesis? why or why not?

Answers: 1

Answer

Physics, 22.06.2019 18:30

Acar starts from rest at a stop sign and reaches a velocity of 25 m/s w in 4 seconds. determine the acceleration of the car. question 3 options: a) 6,25 m/s2 b)6.25 m/s c)100 m/s2 d)100 m/s

Answers: 1

Answer

You know the right answer?

Distinguish between instantaneous speed and average speed. a man drives a car a distance of 200km at...

Questions