The body is thrown at an initial speed of 20 m / s at an angle to the horizontal of 45
| April 8, 2021 | education
The body is thrown at an initial speed of 20 m / s at an angle to the horizontal of 45 degrees. Find the body speed at a height of 7 m above the ground.
To find the speed of the thrown body at the considered height, we use the law of conservation of energy: Ek1 + En1 = Ek0; m * Vx ^ 2/2 + m * g * h1 = m * V0 ^ 2/2, whence we express: Vx = √ (2 * (V0 ^ 2/2 – g * h1)).
Variables and constants: V0 – speed at the moment of throw (V0 = 20 m / s); g – acceleration due to gravity (g ≈ 10 m / s2); h1 – considered height (h1 = 7 m).
Calculation: Vx = √ (2 * (V0 ^ 2/2 – g * h1)) = √ (2 * (20 ^ 2/2 – 10 * 7)) ≈ 16.12 m / s.
Answer: An abandoned body at a height of 7 m should have had a speed of 16.12 m / s.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.
