The velocity of desmond’s car changes from 20 meters/second to 10 meters/second. the change happens in 5 seconds. what’s the acceleration of the car? use . 4 m/s2 2 m/s2 -2 m/s2 -4 m/s2

- 2 m/s²

Explanation:

Acceleration is the rate of change of velocity with time.

Given,

Initial velocity = 20 m/s

Final velocity = 10 m/s

Time = 5s

Change of velocity = Final velocity - Initial velocity = 10 m/s - 20 m/s =  - 10 m/s

Acceleration = = = - 2 m/s²

Here the minus sign (- 2 m/s²) indicates that the acceleration is actually decreasing. This is because the final velocity is lower than the initial velocity.  

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.