Question

По реке плывет баржа со скоростью 4м/c. По барже, перпендикулярно направлению ее движения равномерно бежит мальчик. Время движения мальчика от одного борта до другого 2секунды. Ширина баржи 6метров. Определите скорость мальчика и его перемещение за это время, относительно а) Баржи б) берега.

Answer 1

А) относительно берега
S₁ = L - перемещение мальчика
v₁ = L / t = 6 м / 2 с = 3 м/с - скорость мальчика
б) относительно берега
v₁' = v₁ + v - равенство векторное!
v₁' = √(v₁² + v²) = √((3 м/с)² + (4 м/с)²) = 5 м/с - скорость мальчика
S₁' = v₁' * t = 5 м/с * 2 с = 10 м - перемещение мальчика

Answer 2

скорость баржи относительно берега v1 = 4 м/с

скорость мальчика относительно баржи v2 = Ш / t = 6/2 =3 м/с

скорость мальчика относительно берега по теореме Пифагора

v^2 = v1^2 +v2^2 = 4^2 +3^2 = 25

v = √25 = 5 м/с  - скорость за это время относительно берега.

перемещение

S1 = 4*2 = 8 м

S2 = 3*2 = 6 м

перемешение мальчика относительно берега по теореме Пифагора

S^2 = S1^2  +S2^2 = 8^2 + 6^2 = 100

S = √100 = 10 м

Answer 3

Given Information:

- The barge is moving with a speed of 4 m/s. - The boy is running perpendicular to the direction of the barge's motion. - The time taken by the boy to move from one side of the barge to the other is 2 seconds. - The width of the barge is 6 meters.

Calculating the Boy's Speed:

To calculate the speed of the boy, we can use the formula:

Speed = Distance / Time

The distance covered by the boy is equal to the width of the barge, which is 6 meters. The time taken by the boy is given as 2 seconds. Plugging these values into the formula, we can calculate the speed of the boy:

Speed = 6 meters / 2 seconds = 3 meters per second

Therefore, the speed of the boy is 3 meters per second.

Calculating the Boy's Displacement Relative to:

a) The Barge: The boy's displacement relative to the barge is equal to the width of the barge, which is 6 meters. This is because the boy is running perpendicular to the barge's motion, so his displacement is equal to the width of the barge.

b) The Shore: To calculate the boy's displacement relative to the shore, we need to consider the motion of the barge as well. Since the barge is moving with a speed of 4 m/s, the boy's displacement relative to the shore will be the vector sum of his displacement relative to the barge and the barge's displacement relative to the shore.

The barge's displacement relative to the shore can be calculated using the formula:

Displacement = Speed × Time

The speed of the barge is given as 4 m/s, and the time taken by the boy to move from one side of the barge to the other is given as 2 seconds. Plugging these values into the formula, we can calculate the barge's displacement relative to the shore:

Displacement = 4 m/s × 2 seconds = 8 meters

Therefore, the boy's displacement relative to the shore is the vector sum of his displacement relative to the barge (6 meters) and the barge's displacement relative to the shore (8 meters):

Displacement = 6 meters + 8 meters = 14 meters

Therefore, the boy's displacement relative to the shore is 14 meters.

To summarize: - The speed of the boy is 3 meters per second. - The boy's displacement relative to the barge is 6 meters. - The boy's displacement relative to the shore is 14 meters.

Please note that the information provided is based on the given problem statement, and the calculations are made using the provided data.