The distance travelled by the object during the first 4 seconds is 80 m
<h3>Definition of speed </h3>
Speed is defined as the distance travelled per unit time. Mathematically, it can be expressed as:
Speed = distance / time
With the above formula, we can obtain the distance travelled by the object in the first 4 seconds.
<h3>How to determine the distance travelled </h3>
Speed = distance / time
20 = distance / 4
Cross multiply
Distance = 20 × 4
Distance = 80 m
Complete question:
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The radiations detected by Arno Penzias and Robert Wilson
were the original heat from the Big Bang.
Today, we call those waves the "Cosmic Microwave Background".
I'm not sure, but I think those guys were awarded a Nobel Prize in Physics
for that discovery.
Answer: 1
an object positioned at some height in a gravitational field
Explanation:
Gravitational potential energy of an object is the energy stored due to position of the object or position at certain height relative to zero position.
Gravitational potential energy can also be expressed as object position at some height above or below zero position in a gravitational field
I think 1 and 2 make sense. But 1 make more sense than 2
What models are you talking about

When an opaque obstacle is placed between a source of light and a screen, a shadow of the obstacle is formed on the screen. The kind of shadow depends on the size of the source of light. In other words, the earth casts its shadow on the moon. The solar eclipse occurs when the moon comes between the sun and the earth.