Acky, wearing roller-skates, is standing beside his mailbox when his friend davey skates by at a constant speed of 4m/s. two seconds later, jacky skates after his friend and accelerates uniformly at 2m/s. how long does it take jacky to catch davey?

Explanation:

Let Jacky takes t seconds to catch up with his friend.

Distance traveled by him can be calculated as follows

s =ut + 1/2 a t²

u = 0 , a = 2m / s²

s = .5 x 2 t² = t².

Time during which Davey was in motion is t + 2

Distance covered by him

= 4 ( t + 2 )  

These two distances must be equal due to their meeting .

4(t +2  )= t²,

t² -4t -8 =0

t = 5.46 s

electrical to thermal

weather forecasts are done by collecting data about the current state of the atmosphere mainly the temperature, humidity and wind and using meteorology, to determine the atmosphere that evolves over time. the h and l mean the high and low pressure. the red strip is a warm front. the blue strip is a cold front. the blue and red strip is a stationary front. the purple strip is a occluded front.

explanation: