## Galilean Relativity and Tangential Acceleration

Any help would be greatly appreciated.

1. Two swimmers, John and Emma, start together at the same point on the bank of a wide stream that flows with the speed c (c>v), relative to the water. John swims downstream a distance L and then upstream the same distance. Emma swims so that her motion relative to the earth is perpendicular to the banks of the stream. She swims the distance L and then back the same distance, so that both swimmers return to the starting point. Which swimmer returns first?

2. An automobile whose speed is increasing at a rate of .6 m/s^2 travels along a circular road of radius 20m. When the instantaneous speed of the automobile is 4 m/s, what is the tangential acceleration?

Thanks.
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 what is v? that is the same ether density determining experiment the swimmer going across would win
 No v value given. Just asking you to solve in terms of time I suppose. Variables only.

Any help?