<u>The Weight </u>is a vector whose magnitude is the product of the mass m of the object and the magnitude of the local gravitational acceleration. Its always directed toward the center of the Earth.
Answer:
Atom, smallest unit into which matter can be divided without the release of electrically charged particles.
an element is a pure substance which cannot be broken down by chemical means
Answer:
wave changes its path from its initial direction so this phenomenon is known as Refraction of wave
Explanation:
When wave travels from one medium to other medium the due to change in the speed of the wave propagation it deviates from its initial path.
The deviation of the wave from its initial path is known as refraction of wave
Here we can see that wave incident on medium 1 with some angle with the boundary
Then it enters into other medium and then travels in other direction
So here wave changes its path from its initial direction so this phenomenon is known as Refraction of wave
Answer:Take into account the the Earths gravity is 9.8 meters a second
Explanation:
Gravity pulls down on the ball at g=-9.81 m/s^2. Up is positive, down is negative.The ball started at a certain initial velocity of Vi m/s. Time it took is t=4s. Final velocity is Vf=0 m/s, because at the highest point the ball stops moving.
Vf=(g*t)+Vi
Rearrange for Vi.
Vi=Vf-(g*t)
Vi=0-(-9.81*4)=39.24 m/s (upward)
Think about it this way for the non-mathematical approach. The ball stops at the top. The initial velocity gets reduced by 9.81 m/s every second, and reaches 0 m/s at the top. It took 4 seconds, so 9.81*4 is equal to the initial upward velocity.