Answer: -39.2 m/s or 39.2 m/s directed downwards
Explanation:
This situation is a good example of Free Fall, where the main condition is that the initial velocity must be zero , and the acceleration is constant (acceleration due gravity).
So, in order to calculate the final velocity of the rock just at the moment it hitsthe bottom of the cliff, we will use the following equation:
Where:
is the acceleration due gravity (directed downwards)
is the time it takes to the rock to fall down the cliff
This is the rock's final velocity and its negative sign indicates it is directed downwards
I think its C or D.
Einstein's Nobel winning photoelectric equation.
The higher the work function, the more energy needed to photoeject an electron from the surfface
Try D
Answer:
2.67 m
Explanation:
k = Spring constant = 1.5 N/m
g = Acceleration due to gravity = 9.81 m/s²
l = Unstretched length
Frequency of SHM motion is given by
Frequency of pendulum is given by
Given in the question
The unstretched length of the spring is 2.67 m
Answer:
Explanation:
Given that,
Mass m = 6.64×10^-27kg
Charge q = 3.2×10^-19C
Potential difference V =2.45×10^6V
Magnetic field B =1.6T
The force in a magnetic field is given as Force = q•(V×B)
Since V and B are perpendicular i.e 90°
Force =q•V•BSin90
F=q•V•B
So we need to find the velocity
Then, K•E is equal to work done by charge I.e K•E=U
K•E =½mV²
K•E =½ ×6.64×10^-27 V²
K•E = 3.32×10^-27 V²
U = q•V
U = 3.2×10^-19 × 2.45×10^6
U =7.84×10^-13
Then, K•E = U
3.32×10^-27V² = 7.84×10^-13
V² = 7.84×10^-13 / 3.32×10^-27
V² = 2.36×10^14
V=√2.36×10^14
V = 1.537×10^7 m/s
So, applying this to force in magnetic field
F=q•V•B
F= 3.2×10^-19 × 1.537×10^7 ×1.6
F = 7.87×10^-12 N