The motion of a falling ball towards Earth is due to the
Solution:
The motion of a falling ball towards Earth is due to the gravitational force exerted by the Earth on the ball.
Newton's law of gravitation holds between every two objects on the
Solution:
Newton's law of gravitation is universal and applies to every two objects in the universe.
Numerical value of G is
Solution:
The numerical value of the universal gravitational constant \( G \) is \( 6.673 \times 10^{-11} \, \text{Nm}^2/\text{kg}^2 \).
Gravitational field of Earth is directed
Solution:
The gravitational field of Earth is directed towards the center of the Earth.
_________ was the first scientist who gave the concept of gravitation.
Solution:
Isaac Newton was the first scientist who gave the concept of gravitation.
According to Newton's law of universal gravitation force ∝ _______
Solution:
According to Newton's law of universal gravitation, the force is proportional to the product of the masses and inversely proportional to the square of the distance between them.
Gravitational force is always
Solution:
Gravitational force is always attractive.
Numerical value of..............remains constant everywhere.
Solution:
The numerical value of the universal gravitational constant \( G \) remains constant everywhere.
Gravitation force is..............of the medium between the objects.
Solution:
Gravitational force is independent of the medium between the objects.
Near Earth's surface \( g = \)________
Solution:
Near Earth's surface, the acceleration due to gravity \( g \) is approximately \( 10 \, \text{m/s}^2 \).
Newton's law of gravitation is consistent with Newton's...............law of motion.
Solution:
Newton's law of gravitation is consistent with Newton's third law of motion, which states that for every action, there is an equal and opposite reaction.
Spring balance is used to measure_______
Solution:
A spring balance is used to measure the weight of an object.
Your weight as measured on Earth will be........... on Moon.
Solution:
Your weight as measured on Earth will be decreased on the Moon due to the Moon's weaker gravitational field.
Mass of Earth is________
Solution:
The mass of Earth is approximately \( 6.0 \times 10^{24} \, \text{kg} \).
_________ is a natural satellite.
Solution:
The Moon is a natural satellite of Earth.
A communication satellite completes its one revolution around the Earth in............hours.
Solution:
A communication satellite typically completes one revolution around the Earth in 24 hours.
The velocity of a satellite is.............of its mass.
Solution:
The velocity of a satellite is independent of its mass.
_________are used to put satellites into orbits.
Solution:
Rockets are used to put satellites into orbits.
The critical velocity \( V_c = \)
Solution:
The critical velocity \( V_c \) is given by \( \sqrt{gR} \).
What is the gravitational force of Earth commonly known as?
Solution:
The gravitational force of Earth is commonly known as gravity.
Which formula represents the gravitational force between two masses?
Solution:
The formula representing the gravitational force between two masses is \( F = G \frac{m_1 m_2}{r^2} \).
Which statement is true about \( G \) (universal gravitational constant) and \( g \) (acceleration due to gravity)?
Solution:
The universal gravitational constant \( G \) is constant, while the acceleration due to gravity \( g \) varies depending on the location.
What defines a gravitational field?
Solution:
A gravitational field is defined as a region where a mass experiences gravitational attraction.
Calculate the weight of a 5 kg object on Earth if \( g = 10 \, \text{m/s}^2 \).
Solution:
The weight of a 5 kg object on Earth is calculated as \( W = mg = 5 \, \text{kg} \times 10 \, \text{m/s}^2 = 50 \, \text{N} \).
What is critical velocity?
Solution:
Critical velocity is the horizontal velocity required for a stable orbit around a celestial body.
Sputnik-1 is an example of:
Solution:
Sputnik-1 is an example of an artificial satellite.
What is the natural force that pulls two objects with mass toward each other?
Solution:
Gravity is the natural force that pulls two objects with mass toward each other.
Who formulated the law of universal gravitation after observing an apple fall?
Solution:
Isaac Newton formulated the law of universal gravitation after observing an apple fall.
Gravitational force between two masses is inversely proportional to:
Solution:
Gravitational force between two masses is inversely proportional to the square of the distance between their centers.
Which statement correctly differentiates \( G \) and \( g \)?
Solution:
The universal gravitational constant \( G \) is a constant, while the acceleration due to gravity \( g \) varies with location.
Who first experimentally demonstrated Newton’s law of gravitation?
Solution:
Henry Cavendish was the first to experimentally demonstrate Newton’s law of gravitation.
If the distance between two masses doubles, the gravitational force becomes:
Solution:
If the distance between two masses doubles, the gravitational force becomes one-fourth, as the force is inversely proportional to the square of the distance.
Gravitational field lines around Earth point:
Solution:
Gravitational field lines around Earth point toward Earth’s center.
An object’s weight on the Moon is less than on Earth because:
Solution:
An object’s weight on the Moon is less than on Earth because the Moon’s gravitational field strength is weaker.
Gravitational field strength is defined as:
Solution:
Gravitational field strength is defined as force per unit mass.
Which is NOT a characteristic of gravitational force?
Solution:
Gravitational force does not act only on Earth; it is a universal force.
What is the definition of weight?
Solution:
Weight is defined as the gravitational force acting on an object.
Which formula correctly calculates weight?
Solution:
The formula to calculate weight is \( W = m \times g \), where \( m \) is the mass of the object and \( g \) is the acceleration due to gravity.
What is the SI unit of weight?
Solution:
The SI unit of weight is the Newton (N).
Calculate the weight of a 65 kg person if \( g = 10 \, \text{N/kg} \).
Solution:
The weight of a 65 kg person is calculated as \( W = m \times g = 65 \, \text{kg} \times 10 \, \text{N/kg} = 650 \, \text{N} \).
Why does weight vary on different planets?
Solution:
Weight varies on different planets because the gravitational field strength (\( g \)) differs from planet to planet.
Which law is used to calculate Earth’s mass indirectly?
Solution:
Newton’s Law of Universal Gravitation is used to calculate Earth’s mass indirectly.
Which two forces are equated in the derivation of Earth’s mass?
Solution:
In the derivation of Earth’s mass, the gravitational force and the weight of the object are equated.
What is the formula used to calculate Earth’s mass (\( M_e \))?
Solution:
The formula used to calculate Earth’s mass is \( M_e = \frac{gR^2}{G} \).
What value is used for Earth’s radius (\( R_e \)) in the calculation?
Solution:
The value used for Earth’s radius in the calculation is \( 6.38 \times 10^6 \, \text{m} \).
What is the calculated mass of Earth?
Solution:
The calculated mass of Earth is \( 6.0 \times 10^{24} \, \text{kg} \).
What is the primary cause of ocean tides?
Solution:
The primary cause of ocean tides is the Moon’s gravitational pull.
What are the units of the universal gravitational constant (\( G \))?
Solution:
The units of the universal gravitational constant \( G \) are \( \text{Nm}^2 \text{kg}^{-2} \).
Which term cancels out when equating \( F = \frac{GM_em}{R_e^2} \) and \( F = mg \)?
Solution:
The term \( m \) cancels out when equating \( F = \frac{GM_em}{R_e^2} \) and \( F = mg \).
What is a natural satellite?
Solution:
A natural satellite is a celestial body orbiting another planet naturally.
Which was the first artificial satellite?
Solution:
The first artificial satellite was Sputnik-1.
Geostationary satellites are primarily used for:
Solution:
Geostationary satellites are primarily used for communication.
A geostationary satellite completes one revolution around the Earth in............hours.
Solution:
A geostationary satellite completes one revolution around the Earth in 24 hours.
Orbital velocity of a satellite is given by:
Solution:
The orbital velocity of a satellite is given by \( v = \sqrt{\frac{GM}{R + h}} \).
Critical velocity for a satellite near Earth’s surface is approximately:
Solution:
The critical velocity for a satellite near Earth’s surface is approximately 8 km/s.
The centripetal force for a satellite’s orbit is provided by:
Solution:
The centripetal force for a satellite’s orbit is provided by Earth’s gravitational pull.
The height of a geostationary satellite from Earth’s surface is:
Solution:
The height of a geostationary satellite from Earth’s surface is approximately 42,300 km.
Tides in oceans are caused by gravitational forces of:
Solution:
Tides in oceans are caused by the gravitational forces of both the Sun and the Moon.
If a satellite’s speed is less than orbital velocity, it will:
Solution:
If a satellite’s speed is less than orbital velocity, it will fall back to Earth.
Orbital velocity is defined as the velocity required to:
Solution:
Orbital velocity is defined as the velocity required to maintain a satellite in its orbit.
The orbital speed of a satellite depends on its:
Solution:
The orbital speed of a satellite depends on its altitude (height).
Time period (T) of a satellite depends on:
Solution:
The time period \( T \) of a satellite depends on \( T = 2\pi \sqrt{\frac{r^3}{GM}} \).
Which orbit is used for communication satellites?
Solution:
Geostationary orbit is used for communication satellites.
In the equation \( v = \sqrt{g_h(R+h)} \), \( g_h \) represents:
Solution:
In the equation \( v = \sqrt{g_h(R+h)} \), \( g_h \) represents gravity at height \( h \).
The term \( r \) in satellite motion equations equals:
Solution:
The term \( r \) in satellite motion equations equals \( R + h \).