Primary Science Reading Comprehension – (Worksheet 1)

Read the scientific article below and circle the letter of the correct answers to the questions about it.

Understanding Satellites

Satellites are artificial or natural objects that orbit around larger objects (heavenly bodies) such as planets or stars. The Earth has both natural and artificial satellites orbiting it. The Moon is a natural satellite that orbits the Earth. Artificial satellites are man-made objects or spacecraft that orbit the Earth such as the International Space Station or the Hubble Space Telescope. When we throw a ball or shoot an arrow, they will eventually fall to the ground. This is because the upward or sideways velocity (speed) of such objects is always overtaken by both the downward force of gravity and the friction and drag of the air that makes up Earth’s atmosphere. Satellites however, can remain in orbit because they are traveling sideways or parallel to the Earth’s surface at a velocity high enough that they never fall to the ground. They are also high enough or far enough from the Earth that they are mostly free from the friction and drag of Earth’s atmosphere. The velocity required for a satellite to remain in orbit without falling to Earth is called its orbital velocity. An object’s orbital velocity balances out or overcomes the downward force of gravity. To maintain an orbit around Earth at an altitude of approximately 150 miles requires an orbital velocity of around 17,000 miles per hour. A satellite’s escape velocity is the speed it must travel in order to escape (break free) of a planet’s gravitational pull (leave or break out of orbit) traveling away from the planet instead of merely orbiting it. The escape velocity necessary to break away from orbit around Earth is approximately 25,900 miles per hour.

1. What are satellites? a. Objects that orbit around larger bodies in outer space

b. Objects that always move in a straight line

c. Objects that travel through the solar system

2. What is necessary to achieve Earth orbit? a. The object must be light enough in weight

b. The object’s distance from Earth must be far enough

c. The object must be moving at orbital velocity

3. Thrown objects always fall to Earth because: a. They don’t have wings to provide lift

b. They are solid and weigh too much

c. The downward force from gravity and air friction

4. What kind of satellite is our Moon? a. An artificial satellite

b. A celestial satellite

c. A natural satellite

5. What velocity’s required to leave Earth orbit? a. 17,000 miles per hour

b. 1 million miles per hour

c. 25,900 miles per hour

Name: __________________________________________ Date:__________________ Copyright © 2015 www.studentpuzzles.com

Key to Primary Science Reading Comprehension – (Worksheet 1)

Read the scientific article below and circle the letter of the correct answers to the questions about it.

Understanding Satellites

Satellites are artificial or natural objects that orbit around larger objects (heavenly bodies) such as planets or stars. The Earth has both natural and artificial satellites orbiting it. The Moon is a natural satellite that orbits the Earth. Artificial satellites are man-made objects or spacecraft that orbit the Earth such as the International Space Station or the Hubble Space Telescope. When we throw a ball or shoot an arrow, they will eventually fall to the ground. This is because the upward or sideways velocity (speed) of such objects is always overtaken by both the downward force of gravity and the friction and drag of the air that makes up Earth’s atmosphere. Satellites however, can remain in orbit because they are traveling sideways or parallel to the Earth’s surface at a velocity high enough that they never fall to the ground. They are also high enough or far enough from the Earth that they are mostly free from the friction and drag of Earth’s atmosphere. The velocity required for a satellite to remain in orbit without falling to Earth is called its orbital velocity. An object’s orbital velocity balances out or overcomes the downward force of gravity. To maintain an orbit around Earth at an altitude of approximately 150 miles requires an orbital velocity of around 17,000 miles per hour. A satellite’s escape velocity is the speed it must travel in order to escape (break free) of a planet’s gravitational pull (leave or break out of orbit) traveling away from the planet instead of merely orbiting it. The escape velocity necessary to break away from orbit around Earth is approximately 25,900 miles per hour.

1. What are satellites? a. Objects that orbit around larger bodies in outer space

b. Objects that always move in a straight line

c. Objects that travel through the solar system

2. What is necessary to achieve Earth orbit? a. The object must be light enough in weight

b. The object’s distance from Earth must be far enough

c. The object must be moving at orbital velocity

3. Thrown objects always fall to Earth because: a. They don’t have wings to provide lift

b. They are solid and weigh too much

c. Of the downward force from gravity and air friction

4. What kind of satellite is our Moon? a. An artificial satellite

b. A celestial satellite

c. A natural satellite

5. What velocity’s required to leave Earth orbit? a. 17,000 miles per hour

b. 150 miles per hour

c. 25,900 miles per hour

Name: __________________________________________ Date:__________________ Copyright © 2015 www.studentpuzzles.com