Answer:
15 g
Explanation:
Given,
Plutonium-244 = 30 g
We have to find the gram of Plutonium-244 left after 1 half-life.
We know that the half-life of a radioactive isotope is constant. The half-life of a Radioactive isotope does not depend on the initial amount of isotope.
Now,
After 1 half-life
Plutonium-244 left = 
= 15 g
Hence, 15 g of the Plutonium-244 will be left after 1 half-life.
Answer:
52.47706 mph
54.5 mph
Explanation:
The average speed is given by
Julie's average speed on the way to Grandmother's house is 52.47706 mph
Average speed on the return trip is 54.5 mph
I. Positive acceleration increases velocity. Negative acceleration decreases velocity. runner A sped up until the finish line and then slowed to a stop.
ii. Zero a acceleration implies a constant, unchanging velocity not a zero velocity. runner B achieved some velocity prior to 8s and is moving and must slow down to reach a stop.
iii. None. No aspects of this reasoning are correct. Everything she says is wrong. See iv for what/why.
iv. The sign on acceleration denotes the direction of *change in velocity* not change in direction. The sign on velocity can denote change in direction but only “forward” or “reverse” along a particular path. Cardinal direction is not indicated, generally, by the sign on velocity. It may correspond to North/South situationally but it is not an built-in feature of velocity and its sign. For example, if you are traveling with positive velocity and turn left to continue your journey you still have a positive velocity in the new direction. In fact, if you turn left again, traveling in the opposite direction as the one you started with your velocity would still be positive… in the new direction. The velocity relative to original direction could be said to be negative but that would be a confusing way to describe a journey. Maybe if you stopped the vehicle and moved in reverse, you could meaningfully say velocity was negative.
Explanation:
Kepler's third law gives the relationship between the orbital radius and the orbital period of the planet. Its mathematical form is given by :
Here,
G is gravitational constant
M is mass of sun
It means that the mass of Sun is constant for all planets orbiting the sun, assuming circular orbits.
