Question

Тело движется равномерно со скоростью 3 м/с в течение 20 с, затем в течение 15 с движется с ускорением 2 м/с и останавливается. какой путь оно пройдет за все время движения ?

Answer 1

Весь путь складывается из двух частей: первая часть s=vt=3*20=60 м, а второй участок пути рассчитаем по формуле s=vt+ (at2)/2=3*15+2*225/2=45+225=270 м
значит весь путь 60 м + 280 м=340 м

Answer 2

Calculation of the Total Distance Traveled

To calculate the total distance traveled by an object, we need to consider the two phases of its motion: the first phase where it moves with a constant velocity of 3 m/s for 20 seconds, and the second phase where it decelerates with an acceleration of 2 m/s^2 and comes to a stop in 15 seconds.

In the first phase, the object moves with a constant velocity of 3 m/s for 20 seconds. The distance traveled during this phase can be calculated using the formula:

Distance = Velocity × Time

Substituting the given values, we have:

Distance1 = 3 m/s × 20 s

Now, let's calculate the distance traveled during the first phase:

Distance1 = 3 m/s × 20 s = 60 meters In the second phase, the object decelerates with an acceleration of 2 m/s^2 and comes to a stop in 15 seconds. To calculate the distance traveled during this phase, we can use the equation of motion:

Distance = Initial Velocity × Time + (1/2) × Acceleration × Time^2

Since the object comes to a stop, the final velocity is 0 m/s. Therefore, the equation simplifies to:

Distance2 = (1/2) × Acceleration × Time^2

Substituting the given values, we have:

Distance2 = (1/2) × 2 m/s^2 × (15 s)^2

Now, let's calculate the distance traveled during the second phase:

Distance2 = (1/2) × 2 m/s^2 × (15 s)^2 = 225 meters To find the total distance traveled, we add the distances traveled during the two phases:

Total Distance = Distance1 + Distance2

Substituting the calculated values, we have:

Total Distance = 60 meters + 225 meters = 285 meters

Therefore, the object will travel a total distance of 285 meters during its entire motion.