Question

Дано: t1-5 сек. S1-10000 м. V0-0 м/с t2- седьмая секунда Найти: S7-на седьмую секунду

Answer 1

Т.к. V0= 0м/с, то S=$\frac{at^{2} }{2}$; 10000=$\frac{a5^{2} }{2}$; 20000= a * 25; a=$\frac{20000}{25}$; a=800м/с²; S=$\frac{800* 7 ^{2} }{2}$; S= 19600м.

Answer 2

Given Information:

- t1 = 5 sec - S1 = 10000 m - V0 = 0 m/s - t2 = 7 sec

Finding S7 (distance at the seventh second):

To find the distance at the seventh second (S7), we need to calculate the displacement from t1 to t2 and add it to the initial position (S1).

The displacement (ΔS) can be calculated using the formula: ΔS = V0 * (t2 - t1) + (1/2) * a * (t2 - t1)^2

Since the initial velocity (V0) is 0 m/s, the first term of the equation becomes 0.

Therefore, the equation simplifies to: ΔS = (1/2) * a * (t2 - t1)^2

To find the acceleration (a), we can use the formula: a = 2 * (ΔS - S1) / (t2 - t1)^2

Substituting the given values into the equations, we can find the value of S7.

Calculation:

Given: t1 = 5 sec S1 = 10000 m V0 = 0 m/s t2 = 7 sec

Using the equation ΔS = (1/2) * a * (t2 - t1)^2, we can find the displacement: ΔS = (1/2) * a * (7 - 5)^2

Now, let's find the acceleration (a) using the formula a = 2 * (ΔS - S1) / (t2 - t1)^2: a = 2 * ((1/2) * a * (7 - 5)^2 - 10000) / (7 - 5)^2

Simplifying the equation: a = 2 * (a - 10000) / 4

Multiplying both sides by 4: 4a = 2a - 20000

Subtracting 2a from both sides: 2a = -20000

Dividing both sides by 2: a = -10000

Now that we have the value of acceleration (a), we can substitute it back into the equation for displacement: ΔS = (1/2) * (-10000) * (7 - 5)^2

Simplifying the equation: ΔS = -10000

Finally, we can find S7 by adding the displacement (ΔS) to the initial position (S1): S7 = S1 + ΔS S7 = 10000 + (-10000) S7 = 0 m

Answer:

The distance at the seventh second (S7) is 0 meters.