l energy are to ? What causes it to decrease? Give Topic 4: Force & Momentum ery
ID: 2040247 • Letter: L
Question
l energy are to ? What causes it to decrease? Give Topic 4: Force & Momentum ery rigid frames. Today, cars have "crumple zones" in the front and rear make this change? How is this be related to the fact that an egg that [T4.1] In the past, cars were built with frames wrooden foor will likely shatter, but it will likely stay intact if it fall on T4.2] You drag a heavy suitcase with a broken wheel, accelerati sections falls on a en loor a pillow? ng it a little as you pull. The suitcase exerts a force back What is the relationship between your force on the suitcase and the suitcase's force on you? Why does the accelerate in the direction of your puill as opposed to you accelerating in the direction the suitcase is pulling? Quantitative Spring 2018 PHY 111/113 Topic 3: Energy T3.1] You throw a 0.5 kg ball downwards from an initial height of 2 meters. The ball hits a spring and compresses it dow to the ground, a compression distance of about 30 cm. The spring constant is 5000 J/m2. What was the initial spe you imparted to the ball? assuming no energy losses (all the kinetic energy becomes potential energy once the object has reached a mathematio infinite distance). What is the escape speed for an object on the surface of the moon, whose mass that is a sixth of Earth's mass Mmoon1024 kg and whose radius is about a quarter that of the Earth's Rmoon 1.6 x 100 m? 3.2] The bare minimum vertical speed required for an object to escape from the Earth's gravitational pull is 11.2Explanation / Answer
3.1)
let m = 0.5 kg
h = 2 m
y = 30 cm = 0.3 m
K = 5000 J/m^2
Apply conservation of energy
initial mechanical energy = final mechanical energy
m*g*(h + y) + (1/2)*m*v^2 = (1/2)*k*y^2
0.5*9.8*(2 + 0.3) + (1/2)*0.5*v^2 = (1/2)*5000*0.3^2
==> v = 29.2 m/s
3.2) escape speed on the earth surface,
ve = sqrt(2*G*Me/Re)
escape speed on the moon surface,
vm = sqrt(2*G*Mm/rm)
= sqrt(2*G*(Me/6)/(Re/4))
= sqrt(4/6)*sqrt(2*G*Me/Re)
= sqrt(4/6)*11.2 km/s
= 9.14 km/s
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.