Answer:
The magnitude of change in momentum is (2mv).
Explanation:
The momentum of an object is given by the product of mass and velocity with which it is moving.
Let the mass of ball is m. A tennis player smashes a ball of mass m horizontally at a vertical wall. The ball rebounds at the same speed v with which it struck the wall.
Initial speed of the ball is v and final speed, when it rebounds, is (-v). The change in momentum is given by :
p = final momentum - initial momentum
So, the magnitude of change in momentum is (2mv).
Answer:
0.0000076 grams
Explanation:
We're given the half life of Tritium to be 12.3 years. In order to find out the amount of substabce remaining:
Let's first find how many 'half lives' are in 250 years.
Now what is half life? It means the time taken for a given quantity of an element to lose half it's mass.
So in 12.3 years we can find that The amount of 250 g of Tritium will be 250/2 = 125 g. In 24.6 years we'll have 125/2 = 62.5 g
So now we can devise a formula:
Where m is the remaining amount and n is th number of half lives in the time given.
Using this formula we can calculate:
Doing this calculation we get:
As we can see a very small value remains.
Answer:
Explanation:
From the given information:
radius = 15 m
Time T = 23 s
a) Speed (v) = 
v = 4.10 m/s
b) The magnitude of the acceleration is:
a = 1.12 m/s²
c) True weight = mg
Apparent weight = normal force
From the top;
the normal force = upward direction,
weight is downward as well as the acceleration.
true weight - normal force = ma
apparent weight =mg - ma
= 0.886 m/s²
d)
From the bottom;
acceleration is upward, so:
apparent weight - true weight = ma
apparent weight = true weight + ma
= 1.114 m/s²
Answer:
The observations show a higher velocity than is predicted, mainly in the galaxy's outer regions, indicating that there is more mass in the exterior areas than we can see.
