Boomerang has a curve the airplane propeller is four paddles
Answer: D meteoroid
Explanation:
Meteoroid is the smallest among them. It is a tiny asteroid or the broken-off crumb of comets and sometimes planets. It ranges in size from a grain of sand to boulders 3 feet (1 meter) wide. When meteoroids collide with a planet's atmosphere, they become meteors. If those meteors survive the atmosphere and hit the planet's surface, their remains are called meteorites
TV announcer intend to mean "chnage of speed or velocity" by "High rate of speed" and in Physics domain it would mean "acceleration"
Explanation:
It is common to observe TV announcer saying certain events were occurring “with a high rate of speed”. By saying this they intend to mean that the event was rapid in its occurrence. It can also mean that the change in speed of the happening was very rapid/fast.
However, the same terms connote altogether a different expression in Physics domains. Speed is a scalar quantity with no direction. Hence most of the times speed mean velocity when the direction is also provided. “high rate of speed” would mean a change of velocity per unit time which is acceleration. Hence in Physics domain, the term would stand for acceleration.
Answer:
The acceleration of the rattlesnake, a = 126 m/s²
Explanation:
Given,
The initial velocity of the rattlesnake, u = 1.0 m/s
The final velocity of the rattlesnake, v = 20.0 m/s
The time duration to reach the final velocity, t = 0.15 s
The acceleration of a body defined as the rate of change of velocity by time, or simply the difference of final velocity and initial velocity by time.
The formula for acceleration is
a = (v-u)/t m/s²
Substituting the values in the above equation
a = (20 - 1.0 ) / 0.15
= 126 m/s²
Hence, the acceleration of the rattlesnake is, a = 126 m/s²
Answer:
The oldest stars in spiral galaxies are younger than the oldest stars in elliptical galaxies.
Explanation:
Spiral galaxies have a greater star formation than elliptical galaxies, since the latter contain less gas and dust. Therefore, the rate of creation of new stars is lower in elliptical galaxies. These galaxies are dominated by old stars, with a long evolution. While the spiral galaxies have stars with a faster evolution.