Question

(a) calculate the momentum of a 2150 kg elephant charging a hunter at a speed of 7.50 m/s. kg·m/s (b) compare the elephants momentum with that of a 0.0400 kg bullet fired at a speed of 600 m/s.
\frac{elephants momentum}{bullets momentum}= (c) what is the momentum in kilograms times meters per second of the 90.0 kg hunter running at 7.50 m/s after missing the elephant? kg·m/s

Explanation:

(a) Calculate the momentum of the elephant

Step1: Recall the momentum formula

Momentum \(p = mv\), where \(m\) is mass and \(v\) is velocity.
For the elephant, \(m = 2150\space kg\) and \(v=7.50\space m/s\).

$$p_{elephant}=2150\times7.50$$

Step2: Perform the multiplication

$$p_{elephant}=2150\times7.50 = 16125\space kg\cdot m/s$$

(b) Compare the elephant's and bullet's momentum

Step1: Calculate the bullet's momentum

For the bullet, \(m = 0.0400\space kg\) and \(v = 600\space m/s\). Using \(p=mv\), we have \(p_{bullet}=0.0400\times600=24\space kg\cdot m/s\)

Step2: Find the ratio \(\frac{p_{elephant}}{p_{bullet}}\)

$$ \frac{p_{elephant}}{p_{bullet}}=\frac{16125}{24}=671.875 $$

(c) Calculate the hunter's momentum

Step1: Use the momentum formula

For the hunter, \(m = 90.0\space kg\) and \(v = 7.50\space m/s\). Using \(p = mv\), we get \(p_{hunter}=90.0\times7.50\)

Step2: Perform the multiplication

$$p_{hunter}=90.0\times7.50=675\space kg\cdot m/s$$

Answer:

(a) \(16125\space kg\cdot m/s\)
(b) \(671.875\)
(c) \(675\space kg\cdot m/s\)