## 1B.21

$\lambda=\frac{h}{p}$

Aliya Jain 2B
Posts: 101
Joined: Wed Sep 11, 2019 12:16 am

### 1B.21

1B.21 reads "A baseball must weigh between 5.00 and 5.25 ounces (1 ounce 5 28.3 g). What is the wavelength of a 5.15-ounce baseball thrown at 92 mph?" I understand the basic premise of the question, but I'm kind of confused about the conversations? Can someone explain the initial steps

SVajragiri_1C
Posts: 115
Joined: Thu Jul 11, 2019 12:16 am

### Re: 1B.21

First convert the 5.15 ounces to grams using the conversion factor that is provided. Then you have to convert the 92 mph to meters per second by using the miles to meters conversion factor and the hours to minutes to seconds conversion factors (you might have to look this up online). Then plug the data into De Broglie's equation to solve for the wavelength.

Charisse Vu 1H
Posts: 101
Joined: Thu Jul 25, 2019 12:17 am

### Re: 1B.21

This question is dealing with deBroglie's equation, as it is asking for the wavelength of something that has mass and velocity (momentum). Since the units are not what we want, we must use dimensional analysis to convert ounces to kilograms and miles per hour to meters per second. It is given that one ounce is equivalent to 28.3 grams. You would use dimensional analysis to convert the units from ounces to grams, then from grams to kilograms. There are 1,690.3 meters in one mile, and 3600 seconds in one hour. Using this, you would again use dimensional analysis to convert the units to meters per second. Then, you would substitute these values into deBroglie's equation to find the wavelength.

Camille 4I
Posts: 57
Joined: Sat Aug 24, 2019 12:18 am

### Re: 1B.21

Would I be able to convert to kilograms after proceeding with the equation? I already did the De Broglie equation and am wondering if it is possible to convert these units after doing the calculations.