All o the galaxies are moving in a same speed
Answer:
55 miles / hour = 1.475232 kilometers / minute
Answer: Option <em>a.</em>
Explanation:
Kepler's 2nd law of planetary motion states:
<em>A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time.</em>
It tells us that it doesn't matter how far Earth is from the Sun, at equal times, the area swept out by Earth's orbit it's always the same independently from the position in the orbit.
Complete Question
In an action movie, the villain is rescued from the ocean by grabbing onto the ladder hanging from a helicopter. He is so intent on gripping the ladder that he lets go of his briefcase of counterfeit money when he is 130 m above the water. If the briefcase hits the water 6.0 s later, what was the speed at which the helicopter was ascending?
Answer:
The speed of the helicopter is 
Explanation:
From the question we are told that
The height at which he let go of the brief case is h = 130 m
The time taken before the the brief case hits the water is t = 6 s
Generally the initial speed of the briefcase (Which also the speed of the helicopter )before the man let go of it is mathematically evaluated using kinematic equation as
Here s is the distance covered by the bag at sea level which is zero
=>
=> 
=> 
Answer:
v = √(10gh/7)
Explanation:
Initial gravitational energy = final rotational energy + kinetic energy
PE = RE + KE
mgh = ½ Iω² + ½ mv²
For a solid sphere, I = ⅖ mr².
For rolling without slipping, ω = v/r.
mgh = ½ (⅖ mr²) (v/r)² + ½ mv²
mgh = ⅕ mv² + ½ mv²
mgh = 7/10 mv²
10/7 gh = v²
v = √(10gh/7)