a 7.00 kg cannonball is travelling at a velocity of 75.0 m/s at a height of 80.0 m. what is its kinetic energy?
A) 39,400 J
B) 19,700 J
C) 5500 J
D) 525 J
Answer is 19,700 J
as always, K = 1/2 mv^2
Well, let's not shoot ourselves in the foot here. To calculate the kinetic energy of the cannonball, we need to use a formula. The formula for kinetic energy is 1/2 m v^2, where m is the mass and v is the velocity.
Now, let's plug in the numbers. The mass of the cannonball is 7.00 kg and the velocity is 75.0 m/s. Let me do some quick math...
(1/2) * 7.00 kg * (75.0 m/s)^2 = 19,687.50 J
So, the kinetic energy of the cannonball is approximately 19,700 J. Looks like option B) is the winner here!
To find the kinetic energy of the cannonball, we need to use the formula:
Kinetic Energy = 1/2 * mass * velocity^2
Given:
Mass (m) = 7.00 kg
Velocity (v) = 75.0 m/s
Substituting the values into the formula:
Kinetic Energy = 1/2 * 7.00 kg * (75.0 m/s)^2
Calculating:
Kinetic Energy = 1/2 * 7.00 kg * 5625 m^2/s^2
Kinetic Energy = 1/2 * 7.00 kg * 5625 kg*m^2/s^2
Kinetic Energy = 1/2 * 39375 kg*m^2/s^2
Kinetic Energy = 19687.5 kg*m^2/s^2
Rounding to the nearest whole number, the kinetic energy of the cannonball is approximately 19688 J.
Comparing the answer choices, we can see that option B) 19,700 J is the closest match. Therefore, the correct answer is B) 19,700 J.
To find the kinetic energy of the cannonball, we need to use the formula:
Kinetic Energy = 0.5 * mass * velocity^2
First, we need to calculate the square of the velocity, which is given as 75.0 m/s. Squaring this value gives us 75.0^2 = 5625 m^2/s^2.
Next, we multiply the square of the velocity by half of the mass, which is 0.5 * 7.00 kg = 3.50 kg.
Now, we can calculate the kinetic energy:
Kinetic Energy = 0.5 * mass * velocity^2
= 0.5 * 7.00 kg * 5625 m^2/s^2
= 19687.5 J
Rounded to the nearest whole number, the kinetic energy of the cannonball is 19688 J.
Looking at the given options, the closest value to 19688 J is option B) 19,700 J. Therefore, option B) is the correct answer.