A rock is dropped from a 200 m high cliff. How long does it take to fall (a) the first 100 m and (b) the last 50 m?
The basic equation you want is:
s=at22
Solving for t:
t=2sa−−−√
We’ll assume a=9.8 , so 2a−−√=14.9−−−√≈0.4518
So, for (a)s=100 , so t=0.4518100−−−√=4.518
The total time is 0.4518200−−−√≈6.389
The time to fall 150 m is 0.4518150−−−√≈5.533
So the time to fall the last 50 m is 6.389 - 5.533 = 0.856 seconds
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Answer:
The unit you should use for work done and energy is the joule (J) which is indeed the same as the newton metre (N m).
There is another physical quantity which is the product of force and distance and that is torque or moment of a force.
The unit you should use for torque is the newton metre (Nm) and not the joule.
Naming the units of work done and torque differently helps to emphasis the fact that work done and torque refer to two different physical quantities although the definitions of both quantities have the product of force and distance in them.
work done=force→⋅displacement→ and torque→=force→×displacement→
Hope I helped
Answer:
72
Explanation:
The displacement of an object can be found from the velocity of the object by integrating the expression for the velocity.
In this problem, the velocity of the sport car is given by the expression
In order to find the expression for the position of the car, we integrate this expression. We find:
where C is an arbitrary constant.
Here we want to find the displacement after 3 seconds. The position at t = 0 is
While the position after t = 3 s is
Therefore, the displacement of the car in 3 seconds is
Answer:
The number of atoms are 
.
Explanation:
Given that,
Diameter 
Distance = 2.60 cm
We calculate the number of atoms
Using formula of numbers of atoms
Hence, The number of atoms are .
