An example of a balanced force is two cards leaning against each other and not falling over, or two football players blocking each other but neither overpowering the other. An example of an unbalanced force is two cards leaning on each other then falling over, or two football players blocking each other, then one tackles the other.
Answer:
Explanation:
a ) work done by gravitational force
= mg sinθ ( d + .21)
Potential energy stored in compressed spring
= 1/2 k x²
= .5 x 431 x ( .21 )²
= 9.5
According to conservation of energy
mg sinθ ( d + .21) = 9.5
3.2 x 9.8 x sin 30( d + .21 ) = 9.5
d = 40 cm
b )
As long as mg sin30 is greater than kx ( restoring force ) , there will be acceleration in the block.
mg sin30 = kx
3.2 x 9.8 x .5 = 431 x
x = 3.63 cm
When there is compression of 3.63 cm in the spring , block will have maximum velocity. there after its speed will start decreasing.
X ray is one of the electromagnetic waves.
As per Clark Maxwell's electromagnetic theory, all the electromagnetic waves move with the velocity of light i.e c= 3×10^8 m/s
In case of electromagnetic waves,the electric field and magnetic field are perpendicular to each other as well as perpendicular to the direction of propagation.The electromagnetic waves exhibit the property of polarisation. Hence they are transverse in nature.
Hence the best statements about X- ray will be-
1- X -rays are electromagnetic waves
2-X-rays are transverse transverse waves
3- X- rays travel at the speed of light.
We don't know that at all. The 3rd law says that the REaction is opposite and EQUAL to the action. We don't know where that "twice as much" comes from.
Acceleration is the rate of change of velocity of an object. where a is acceleration, v is the final velocity of the object, u is the initial velocity of the object and t is the time that has elapsed. This equation can be rearranged to give: v = u + at.