Answer:
Explanation:
It is given that,
Speed of the projectile is 0.5 v. Let h is the height above the ground. Using the first equation of motion to find it.
Initial speed of the projectile is v and final speed is 0.5 v.
g is the acceleration due to gravity
Let h is the height above the ground. Using the second equation of motion as :
So, the height of the projectile above the ground is 
. Hence, this is the required solution.
Answer:
c.
Explanation:
Initial velocity of cheetah,u=1 m/s
Time taken by cheetah =4.8 s
Final velocity of cheetah,v=28 m/s
We have to find the acceleration of this cheetah.
We know that
Acceleration,
Where v=Final velocity of object
u=Initial velocity of object
t=Time taken by object
Using the formula
Then, we get
Acceleration, a=
Acceleration=
Hence, the acceleration of cheetah=
Answer:
Air is a mixture.
Explanation:
Air is a homogeneous mixture. It is made up of gaseous substances such as nitrogen, oxygen, and smaller amounts of others.
Carbon dioxide is a pure substance, not a mixture.
Carbon is another pure substance, it cannot be separated into other substances.
Oxygen is just oxygen, it does not contain any other substance.
The work function is what we call the minimum energy that is required by an electron to leave the metal target in the photoelectric effect.
The weight changes but the mass will stay the same.
