PHYSICS
HIGH SCHOOL

Answer:

Answer:

Some atoms do not have a proton.

Protons have about same mass as electrons.

Protons have the magnitude of charge as neutrons, but are opposite in sign.

Explanation:

Protons are the positive charge particles which are present inside the nucleus and has a mass equal to neutron.

an atom has equal number of electrons and protons hence it is not possible that atom is found in a state where is does not have any proton.

The mass of proton is equal to that of neutron but not electron. Protons are heavier than that of electrons.

Protons are the positively charged particles whereas neutrons do not have any charge present in it.

Hence the selected three options about protons are false.

MIDDLE SCHOOL

James is setting up a fish tank. He is buying a breed of goldfish that typically grows to be 12 inches long . It's recommended that there be 1 gallon of water for every inch of fish length in the tank . What is the recommended ratio of gallons of water per fully grown gold fish in tank ?

12:12 is the ratio because each fish can grow up to be 12 inches long so 12 gallons would be in the tank per fish.

The recommended ratio of gallons of water per fully grown goldfish in a tank is 12:1. This means for every goldfish that grows up to 12 inches, there should be 12 gallons of water in the tank.

James is **setting** up a fish tank and planning to house a breed of goldfish that typically grows to be 12 inches long. Considering the recommendation, there should be 1 gallon of water for every inch of fish length in the tank. Therefore, for a fully grown goldfish of 12 inches, James will require 12 gallons of water per goldfish - this is the **recommended** ratio of gallons of water per fully grown goldfish in the **tank**.

#SPJ2

COLLEGE

An airplane is flying at Mach 1.48 at an altitude of 7,800.00 meters, where the speed of sound is v = 311.83 m/s. How far away from a stationary observer will the plane be when the observer hears the sonic boom? (Enter the total distance in m.)

Answer:

The plane will be 11545.46 m far when the observer hears the sonic boom

Explanation:

Step 1: Data given

Altitude of the plane = 7800 meters

speed of sound = 311.83 m/s

Step 2:

The mach number M = vs/v

This means v/vs = 1/M

Half- angle = ∅

sin∅= v/vs

∅ = sin^-1 (v/vs)

∅ = sin^-1 (1/M)

∅ = sin^-1(1/1.48)

∅= 42.5 °

tan ∅ = h/x

⇒ with h= the altitude of the plane = 7800 meter

⇒ with x = the horizontal distance moved by the plane

x = h/tan ∅

x = 7800 / tan 42.5

x = 8512.2 meters

d = the distance between the observer and the plane when the observer hears the sonic boom is:

d = √(8512.2² + 7800²)

d = 11545.46 m

The plane will be 11545.46 m far when the observer hears the sonic boom

HIGH SCHOOL

What is the weight on earth of a girl with a mass of 41 kg?

90.3895 would be the answer if you convert it to pounds

HIGH SCHOOL

What is the efficiency of her body when a cyclist expends 1000 w of power to deliver mechanical energy to the bicycle at the rate of 100w?

Given: Energy input = 100 W

Energy output = 1000 W

Formula: Efficiency = Energy Output/Energy Input x 100 %

Efficiency = 100 W/1000 W x 100 %

Efficiency = 10 %

Energy output = 1000 W

Formula: Efficiency = Energy Output/Energy Input x 100 %

Efficiency = 100 W/1000 W x 100 %

Efficiency = 10 %