Answer:
v = 7.67 m/s
Explanation:
Given data:
horizontal distance 11.98 m
Acceleration due to gravity 9.8 m/s^2
Assuming initial velocity is zero
we know that

solving for t
we have

substituing all value for time t

t = 1.56 s
we know that speed is given as


v = 7.67 m/s
The energy carried by the incident light is

where h is the Planck constant and f is the frequency of the light. The threshold frequency is the frequency that corresponds to the minimum energy needed to eject the electrons from the metal, so if we substitute the threshold frequency in the formula, we get the minimum energy the light must have to eject the electrons:
Answer:
The longest wavelength of light that is capable of ejecting electrons from that metal is 1292 nm.
Explanation:
Given that,
Wavelength = 400 nm
Energy 
We need to calculate the longest wavelength of light that is capable of ejecting electrons from that metal
Using formula of energy


Put the value into the formula



Hence, The longest wavelength of light that is capable of ejecting electrons from that metal is 1292 nm.
Answer:
1. Recollapsing universe
2. Critical universe
3. Coasting universe
Explanation:
Recollapsing universe has dark matter density greater than critical density. While critical universe has its matter density equal to the critical sensity. Coasting universe on the other hand has much smaller matter density compared to critical density.
Note that the critical density is approximately 10^-20 grams/cm3
Answer:The net force acting on the car is 3×103 Newtons
Explanation: