Which of the following is not true about centripetal force? Check all that

A car travels from Boston to Hartford in 4 hours. The two cities are 240 kilometers apart. What was the average speed of the car

Y_Kistochka [10]

Answer:

Average speed is 60 km/hour

Explanation:

When we need to calculate average speed, we use this equation:

$V = \frac{x_{f} - x_{o}}{t_{f} - t_{o}}$

Where: $x_{o} = 0 km$ position at the beginning

$x_{f} = 240 km$ at the end

$t_{o} = 0 hours$

$t_{f} = 4 hours$

Then: $V = \frac{240 km - 0 km}{4 hours - 0 hours}$

$V = \frac{240 km}{4 hours}$

Finally V = 60 km/hour

6 0

3 years ago

Help please (20 pts) I think it's C

gregori [183]

Answer:

I'm not sure it is c I'm sure it is d

6 0

3 years ago

# A cheetah can start from rest and attain the velocity 72km/h in 2 seconds. Calculate the acceleration of cheetah

yan [13]

Answer:

Explanation:

Solution,

When a certain object comes in motion from rest, in the case, initial velocity = 0 m/s

Initial velocity ( u ) = 0 m/s

Final velocity ( v ) = 72 km/h ( Given)

We have to convert 72 km /h in m/s

$72 \: km \: per \: hour$

$= 72 \times \frac{1000}{60 \times 60}$

$= 20$ m/s

Final velocity ( v ) = 20 m/s

Time taken ( t ) = 2 seconds

Acceleration (a) = ?

Now,

we have,

$a = \frac{v - u}{t}$

$a = \frac{20 - 0}{2}$

$a = \frac{20}{2}$

$a = 10$ m/s ^2

Hope this helps...

Good luck on your assignment..

7 0

3 years ago

Suppose I have a vector that is 7 units long and that makes an angle of +30 degrees from the positive x-axis. I want to add to t

Vinil7 [7]

Answer:

sum of these two vectors is 6.06i+3.5j-3.5i+6.06j = 2.56i+9.56j

Explanation:

We have given first vector which has length of 7 units and makes an angle of 30° with positive x-axis

So x component of the vector $=7cos30^{\circ}=7\times 0.866=6.06$

y component of the vector $=7sin30^{\circ}=7\times 0.5=3.5$

So vector will be 6.06i+3.5j

Now other vector of length of 7 units and makes an angle of 120° with positive x-axis

So x component of vector $=7cos120^{\circ}=7\times -0.5=-3.5i$

y component of the vector $=7sin120^{\circ}=7\times 0.866=6.06j$

Now sum of these two vectors is 6.06i+3.5j-3.5i+6.06j = 2.56i+9.56j

5 0

4 years ago

Why are we mentley unstable to time travle

leva [86]

Answer:

Mental time travel has been studied by psychologists, cognitive neuroscientists, philosophers and in a variety of other academic disciplines. Major areas of interest include the nature of the relationship between memory and foresight, the evolution of the ability (including whether it is uniquely human or shared with other animals), its development in young children, its underlying brain mechanisms, as well as its potential links to consciousness, the self, and free will.

Explanation:

8 0

3 years ago