Answer: Air exerts forces on falling objects near Earth's surface.
Explanation: Objects falling near the earth surface are rarely in free fall due to the force exerted by air on falling object near the earth( air resistance).
The acceleration of free fall tend to pull the body towards the earth surface while air resistance (drag) tends to act in the opposite direction.
Given that the weight of the body is always constant.
The drag acts in the upward direction, thereby negating the downward weight of the object.
From Newton's Second law:
Force = mass × acceleration due to gravity
Acceleration = force / mass
The net force acting on the object becomes :
(Downward weight - upward drag)
This hampers the free fall of the object due to gravity.
Answer:
(a) decrease
Explanation:
Viscosity is the resistance which occur to flow of the fluid.
More the inter molecular forces between particles of the liquid, more the viscosity of liquid.
<u>Effect of temperature on viscosity:-</u>
Viscosity decreases with the increase in the temperature as forces among the particles decrease on increasing temperature. The kinetic energy of the particles of the liquid increases causing to move in more random motions and thus weaker inter molecular forces and this offer less resistance to the flow.
<u>Hence, viscosity of the liquids decrease with the increasing temperature.</u>
Thermohaline circulation (THC) is mainly caused by global density from gradients created by surface heat and freshwater fluxes
Answer:
Electromagnetic cranes are used to separate copper from iron in a scrap yard. The current is switched on to energies the electromagnet and pick up the iron pieces from the scrap. Then these iron pieces are moved to another position, the electromagnet in switched off and the iron pieces are released.
Explanation:
Answer: v = 43.98 m/s
Explanation: 22 + 15.7x1.4 = 43.98.
Hope this helps!