Using V= vo +at with Vo = 0 and a= 4m/sec2.
V= 0+ 4x8= 32m/s
Answer:
Mass of ball = 3.0102 Kg.
Explanation:
Potential energy at height h is given by
PE = mgh
where m is the mass of the body
g is the the acceleration due to gravity whose value is 9.8 m/s^2
h is the height from surface level
PE is potential energy
In the problem given h = 2 meters
PE = 59 joules
59 = m*9.8*2
=> m = 59/9.8*2 = 3.0102 Kg
Thus, mass of ball is 3.0102 Kg.
Answer:
friction is a force that is against motion. friction happens when two objects or a object and surface rub against each other. since friction acts against motion, it stop objects from moving.
Answer:
the answer would be A and B
Answer:
this is violation of II law of thermodynamics
Explanation:
As per 2nd law of thermodynamics we know that heat always flows from high temperature to low temperature
If heat flows from low temperature to high temperature then it is only possible when some external work is done on the system
So here it says that initially two blocks are at 10 degree C and 20 degree C
Now the cool object will become cooler and hot object becomes hotter
which shows that heat is flowing from low temperature to high temperature
So this is violation of II law of thermodynamics