Can someone help me with these questions? 1. used the Sun to measure Earth’s size

2. proposed model of the solar system with Earth revolving around Sun

3. discovered that planets moved in ellipses

4. discovered four moons of Jupiter

5. made predictions about comets

6. discovered that the universe is expanding

7. came up with the most accepted theory about how the Earth’s and Moon’s tilts were formed

8. educated the general public on the universe

9. proposed that laws of physics applied throughout the universe


A) Einstein
B) Hartmann
C)Hawking
D)Copernicus
E)Kepler
F)Hubble
G)Eratosthenes
H)Halley
I)Galilei

What are the three ways that an object can accelerate

The frequency of vibrations of a vibrating violin string is given by f = 1 2l t ρ where l is the length of the string, t is its tension, and ρ is its linear density.† (a) find the rate of change of the frequency with respect to the following. (i) the length (when t and ρ are constant) (ii) the tension (when l and ρ are constant) (iii) the linear density (when l and t are constant) (b) the pitch of a note (how high or low the note sounds) is determined by the frequency f. (the higher the frequency, the higher the pitch.) use the signs of the derivatives in part (a) to determine what happens to the pitch of a note for the following. (i) when the effective length of a string is decreased by placing a finger on the string so a shorter portion of the string vibrates df dl 0 and l is ⇒ f is ⇒ (ii) when the tension is increased by turning a tuning peg df dt 0 and t is ⇒ f is ⇒ (iii) when the linear density is increased by switching to another string df dρ 0 and ρ is ⇒ f is ⇒

A0.750 kg aluminum pan is removed from the stove and plunged into a sink filled with 10.0 kg of water at 293 k. the water temperature quickly rises to 297 k. what was the initial temperature of the aluminum pan? the specific heat of aluminum is ca = 900 j/(kgk) and water is cw = 4190 j/(kgk)