The force needed to accelerate an elevator upward at a rate of 
is 2000 N or 2 kN.
<u>Explanation:
</u>
As per Newton's second law of motion, an object's acceleration is directly proportional to the external unbalanced force acting on it and inversely proportional to the mass of the object.
As the object given here is an elevator with mass 1000 kg and the acceleration is given as , the force needed to accelerate it can be obtained by taking the product of mass and acceleration.
So 2000 N or 2 kN amount of force is needed to accelerate the elevator upward at a rate of .
Answer:
D
Explanation:
Political scientists use political models to describe the political climate, which is an aggregate mood or opinion of a political society at a point in time.
I this is tricky one sec.. I would go with b
Answer:
The temperature reported by a thermometer is never precisely the same as its surroundings
Explanation:
In this experiment to determine the specific heat of a material the theory explains that when a heat interchange takes place between two bodies that were having different temperatures at the start, the quantity of heat the warmer body looses is equal to that gained by the cooler body to reach the equilibrium temperature. <u>This is true only if no heat is lost or gained from the surrounding.</u> If heat is gained or lost from the surrounding environment, the temperature readings by the thermometer will be incorrect. The experimenter should therefore keep in mind that for accurate results, the temperature recorded by the thermometer is similar to that of the surrounding at the start of the experiment and if it differs then note that there is either heat gained or lost to the environment.
