An object is thrown vertically upwards with a speed of 30 m/s. How high will it

An object is thrown vertically upwards with a speed of 30 m/s. How high will it rise before coming to rest momentarily?

An object is thrown vertically upwards with a speed of 30 m/s. How high will it rise before coming to rest momentarily?

Correct Answer: 45 m

Step 1: Identify the initial speed (u) of the object. In this case, u = 30 m/s.
Step 2: Recognize that at the highest point, the final speed (v) will be 0 m/s.
Step 3: Understand that the acceleration due to gravity (g) is acting downwards, so we use g = 9.8 m/s².
Step 4: Use the formula for height (h) which is h = (v² - u²) / (2g).
Step 5: Substitute the values into the formula: h = (0² - 30²) / (2 * -9.8).
Step 6: Calculate 30² which is 900, so now we have h = (0 - 900) / (2 * -9.8).
Step 7: Calculate 2 * -9.8 which is -19.6, so now we have h = -900 / -19.6.
Step 8: Divide -900 by -19.6 to find h. This gives h = 45.92 m.
Step 9: Round the answer to the nearest meter, which is approximately 45 m.

Kinematics – The question tests the understanding of kinematic equations related to motion under constant acceleration, specifically vertical motion under gravity.
Energy Conservation – It also touches on the concept of energy conservation, where kinetic energy is converted to potential energy at the highest point.