Answer:
Explanation:
The complete question is here.
A spring is compressed between two objects with unequal masses, m and M, held together. The objects are initially at rest on a horizontal friction less surface. When released, which of the following is true?
a) Kinetic energy is same as before being released
b) The total final kinetic energy is zero.
c) The two objects have equal kinetic energy.
d) The speed of one object is equal to the speed of other.
e) The total final momentum of two objects is zero.
So option e) the total final momentum of two objects is zero.
Answer: 40 Newton
Explanation:
Mass of baseball = 20 kg
Velocity of baseball = 20 m/s.
Time taken for throwing = 10 seconds
Since acceleration is the rate of change of velocity per unit time
i.e Acceleration = velocity / time taken
Acceleration = (20 m/s / 10seconds)
Acceleration = 2m/s^2
Now, force required to throw the baseball is a product of mass and acceleration
i.e Force = Mass x acceleration
Force = 20 kg x 2m/s^2
Force = 40Newton
Thus, 40 newton of force is required to throw baseball to reach the plate
Answer: reliable
Explanation:
Reliable (marketing research) information is collected from questions (measurements) that are free from systematic or statistical error. An absence of systematic error implies that the respondents (i.e., the sampled people) who answer questions actually understand what the questions were asking.
Answer:
Amount of radioactive particles left after 60 years = 100 particles.
Explanation:
Amount of radioactive particles before 60 years = 400
Amount of radioactive particles present today = 200
That is radio active particles reduced to half. That is 60 years is half life of this radio active material.
After 60 years this 200 radio active particles will reduce to half.
Amount of radioactive particles left after 60 years = 0.5 x 200 = 100 particles.
We use the formula,
Given, 
and 
.
Substituting these values, we get
.
As Jupiter were a perfect sphere, therefore the volume of sphere is given by
Here, r is the radius of sphere.
Substituting the value of volume we get
.
The diameter is twice of radius, thus the diameter of Jupiter would be
