You will use the height of the bridge from the ground.
Solution:
Formula to be used is y=Viy(t)+g(t^2)/2
Where:
Vi=initial velocity which is 0 m/s
y=10 m
Gravitational acceleration or g =9.8m/s^2
T= time you need
Substitute all the given to the formula
10m=(0m/s)(t)+(9.8m/s^2)(t^2)/2
10mx2=9.8m/s^2(t^2)
Now isolate the variable you want to find which is T or time
10mx2/9.8m/s^2=t^2
20m/9.8m/s^2=t^2
Square root of 2.04= square root of t^2
T=1.43 secs
The answer is 1.43 seconds
Answer:
final kinetic energy of the hammer is 10 kJ
Explanation:
As we know that there is no non conservative force on the system
So here we can use the theory of mechanical energy conservation
So we will have
here we know that
from above expression now
so final kinetic energy of the hammer is 10 kJ
Answer: D. places where the magnetic field strength is either greater or less than the expected strength.
Explanation:
Magnetic anomaly refers to the change in the magnitude of the magnetic field of the Eatth with respect to the location's expected value.
Magnetic anomalies are places where the magnetic field strength is either greater or less than the expected strength. Therefore, the correct option is D.
Answer:
b. Both stars will have the same shift.
Explanation:
It's a very simple problem to solve. Star 1 is approaching toward Earth with a speed v, so let's assume that the change in Doppler Shift is +F and Star 2 is moving away so the change in Doppler shift is -F. But it's time to notice the speed of both stars and that is same but only directions are different. speed is the main factor here. The magnitude of both shifts is F as we can see and + and - are showing there direction of motion. So, because of same amount of speed, both stars will have same shift magnitude. (Just the directions are different)
Answer:
Total energy is constant
Explanation:
The laws of thermodynamics state that thermal energy (heat) is always transferred from a hot body (higher temperature) to a cold body (lower temperature).
This is because in a hot body, the molecules on average have more kinetic energy (they move faster), so by colliding with the molecules of the cold body, they transfer part of their energy to them. So, the temperature of the hot body decreases, while the temperature of the cold body increases.
This process ends when the two bodies reach the same temperature: we talk about thermal equilibrium.
In this problem therefore, this means that the thermal energy is transferred from the hot water to the cold water.
However, the law of conservation of energy states that the total energy of an isolated system is constant: therefore here, if we consider the hot water + cold water as an isolated system (no exchange of energy with the surroundings), this means that their total energy remains constant.
