Force (N) = mass (kg) x velocity (m/s) / time (s)
Answer:
Speed, mass and acceleration
Explanation:
A scalar quantity is a quantity that has only magnitude but no direction while a vector quantity has both magnitude and direction.
According to the question, the row that has two scalars and one vector is speed, mass and acceleration.
The two scalars in this row are speed and mass while the vector quantity there is the acceleration.
Acceleration has direction since it possess direction. A body accelerating will do so in a particular direction. Speed and mass doesn't possess any direction. Mass only specify the magnitude of the body but no clue as to which direction is the body moving towards.
Speed also only specify the
total distance covered with respect to time but not the direction of the direction.
Answer:
Explanation:
As it’s difficult to catch it from up.
Gravitational force will pull us when we jump.
If gravity was not there, he could catch the ball. But he will float in the sky after that.
That’s the answer
Answer:
a) diffraction
Explanation:
Diffraction occurs when waves pass through small openings, around obstacles or sharp edges.When an opaque object is between the point of light and a screen, the border between the shaded and illuminated regions on the screen is not defined. A careful inspection of the scrubber shows that a small amount of light is diverted to the shaded region. The region outside the shadow contains bright and dark altered bands, where the intensity of the first band is brighter than the region of uniform illumination.
75.17 mg of the radioactive substance will remain after 24 hours.
Answer:
Explanation:
Any radioactive substance will obey the exponential decay behavior. So according to this behavior, any radioactive substance will be decaying in terms of exponential form of disintegration constant and Time.
Disintegration constant is the rate of decay of radioactive elements. It can be measured using the half life time of the radioactive element .While half life time is the time taken by any radioactive element to decay half of its concentration. Like in this case, at first the scientist took 200 mg then after 17 hours, it got reduced to 100 g. So the half life time of this element is 17 hours.
Then Disintegration constant = 0.6932/Half Life time
Disintegration constant = 0.6932/17=0.041
Then as per the law of disintegration constant:

Here N is the amount of radioactive element remaining at time t and
is the initial amount of sample, x is the disintegration constant.
So here,
= 200 mg, x = 0.041 and t = 24 hrs.
N = 200 ×
=75.17 mg.
So 75.17 mg of the radioactive substance will remain after 24 hours.