The average velocity of Sandy is given by the total distance covered S divided by the total time taken t:
The total distance covered is
while the total time taken is 2 hours + half an hour (for the rest) + 1 hour and half, so
Therefore, the average velocity is
There is a threshold frequency for each metal, and only light of a frequency higher than this threshold causes electrons to be emitted from the metal surface.
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.
Answer:
1.24 x 10 to the 5 ev = 124,000 ev its B
Explanation:
E = hc/lambda = 1.24 ev-micrometer/1.0x10 to the -5 micrometers = 1.24 x 10 to the 5 ev = 124,000 ev
h = Planck's constant = 6.626 × 10 to the -34 joule·s
c = speed of light = 2.998 × 10 to the 8 m/s
lambda is the given wavelength
E is the desired photon energy
Answer:
Subtract the atomic number from the mass number
Explanation:
The number of neurons in an atom is equal to the difference between the atomic number and the mass number
