Astronomy
Earth rotates 15° per hour. How many degrees does it rotate in 2.5 hours?
37.5°
Name the compound: Na₂SO₄
Sodium sulfate
Cross Aa × aa. What fraction of offspring show the dominant trait?
1/2
What is the unit of force?
Newton (N)
What does CPU stand for?
Central Processing Unit
If it’s New Moon, what phase will it be about 1 week later?
First Quarter (about 7 days later).
Balance: _H2+_Cl2→_HCl
H2+Cl2→2HCl
Microscope: 40× objective and 10× eyepiece. Total magnification?
40×10=400
A 10 N force acts on an area of 2 m². What pressure is produced?
P=F/A=10/2=5 Pa
How many loop runs? for(i=0; i<100; i+=5)
20
A light-year measures what: time or distance? And what is it?
Distance — how far light travels in 1 year.
Balance: Al + O₂ → Al₂O₃
4Al + 3O₂ → 2Al₂O₃
A bacteria population doubles every 3 hours. Starting at 500, how many after 9 hours?
500×8=4000
A 2.0 kg object accelerates at 3.0 m/s². What net force acts on it?
F=ma=2.0×3.0=6.0 N
A screen is 320×240 pixels. How many total pixels?
76,800
f a planet’s orbital period is 8 years, what is its average distance from the Sun in AU use P^2=a^3
P^2=64=a^3
a=4 AU.
Find molarity: 9.0 g NaOH (40 g/mol) in 0.75 L.
moles= grams given/ grams per mole
Molarity = moles/ liters
moles=9.0/40=0.225
M=0.225/0.75=0.30M
A cube-shaped cell has side length 2 mm. Find its surface area : volume ratio.
3:1
A ramp rises 3 ft for every 12 ft of horizontal run. If the ramp’s length (hypotenuse) is LL, what is LL for 48 ft of horizontal run?
12 root 17
How many 8-bit binary strings have exactly 3 ones? same as 8 choose 3
56
A probe travels 17 km/s. About how far does it travel in 1 day? (answer in km)
17×86,400=1,468,800km (≈ 1.47 million km)
In a reaction, the number of molecules of A is always 3 more than twice the number of molecules of B. If the total number of molecules is 51, how many molecules of B are there?
B = 16 (and A=35)
A heart rate is 72 beats/min. How many beats in 2.5 hours?
10,800
A motor uses 200 J of electrical energy to do 150 J of useful work. What is its efficiency?
150/200=0.75⇒ 75%
x = 3
y = 10
while x < y{
y = y - x
x = x + 1}
print(x, y)
prints 5 3