Answer:
D. must have a moon
Explanation:
Scientists say that a planet must orbit a star, must be round, and must be big enough so its gravity clears its orbit of other objects. Therefore, the statement that is not a requirement for a planet is
D. must have a moon
For example, Mercury and Venus are planets with no moons.
Answer:
The gravitational force between m₁ and m₂, is approximately 1.06789 × 10⁻⁶ N
Explanation:
The details of the given masses having gravitational attractive force between them are;
m₁ = 20 kg, r₁ = 10 cm = 0.1 m, m₂ = 50 kg, and r₂ = 15 cm = 0.15 m
The gravitational force between m₁ and m₂ is given by Newton's Law of gravitation as follows;
Where;
F = The gravitational force between m₁ and m₂
G = The universal gravitational constant = 6.67430 × 10⁻¹¹ N·m²/kg²
r₂ = 0.1 m + 0.15 m = 0.25 m
Therefore, we have;
The gravitational force between m₁ and m₂, F ≈ 1.06789 × 10⁻⁶ N
Answer:
True
Explanation:
Convection simply means the transfer of heat resulting from the movement of the molecules of fluid, which can be liquid or gas.
Convection can either be natural or forced. natural convection occurs by a natural means ,such as the difference in density of warm air and cool air. This occurs when the cooler air falls and the warmer air rises.
However in forced convection, the fluid is agitated by an external force eg a fan or pump.
Answer:
It has less mass than the car
Explanation:
Both car and bug have the same amount of force acting on them. As the bug mass is much smaller, it sees a greater acceleration
F = ma
Answer:
Coefficient of dynamic friction= md= 0.09931
Explanation:
To determine the coefficient of dynamic friction we must first match the friction force that is permendicular to the normal force of the block and opposite to the drag force, to the component of the drag force in this same direction. This component on the X axis of the drag force will be:
F= 90N × cos(30°) = 77.9423N
This component on the X axis of the drag force must be equal to the dynamic friction force that is equal to the coefficient of dynamic friction by the normal force of the block weight:
F= md × m × g= 77.9423N
m= mass of the block
md= coefficient of dynamic friction
g= gravity acceleration
F= md × 80kg× 9.81 (m/s²)= 77.9423(kg×m/s²)
md= (77.9423(kg×m/s²) / 784.8 (kg×m/s²)) = 0.09931
