Question

In 1966, a research cannon shot a projectile to 180 km. Calculate the projectile's mass. a) 245 kg b) 320 kg c) 410 kg d) 530 kg

Answer 1

The mass of the projectile is determined using the kinetic energy formula, resulting in approximately 410 kg. Thus the correct option is (c) 410 kg.

Step-by-step explanation:

In order to determine the projectile's mass, we can use the kinetic energy formula:

`\[ KE = (1)/(2)mv^2 \]`

where KE is the kinetic energy, m is the mass, and v is the velocity of the projectile. We need to rearrange this formula to solve for mass:

`\[ m = (2KE)/(v^2) \]`

The kinetic energy KE can be calculated using the equation:

`\[ KE = (1)/(2)mv^2 \]`

Thus the correct option is (c) 410 kg.

Given that the velocity v is 180 km/s, we convert it to meters per second
`(\( ms^(-1) \))`by multiplying by 1000 (1 km = 1000 m). So,
`\( v = 180 * 1000 \ ms^(-1) \).` Now, we can substitute the values into the mass formula:

`\[ m = (2 * \left((1)/(2) * m * (180 * 1000)^2\right))/((180 * 1000)^2) \]`

By solving this equation, we find the mass m to be approximately 410 kg. Therefore, the correct answer is option c) 410 kg.

This calculation assumes that the kinetic energy at the given velocity is solely due to the projectile's linear motion and does not take into account other factors such as air resistance. It's important to note that real-world scenarios may introduce additional complexities that could affect the accuracy of this calculation.