Answer:
2 minutes or 120 seconds
Explanation:
The answer is 2 minutes or 120 seconds because 36 km is 36000 m and 36000 divided by 300 is 120, so the answer is 120 seconds, and converted to 2 minutes. Hope it helps!
Inertia IS always present. Inertia is NOT the force that causes objects to continue moving in circles, that is centripetal force. Centripetal force is NOT always present. Centripetal force DOES pull objects toward the center of a circle. <span> Inertia and centripetal force DOES cause circular motion. Thank you and eat sand fren ;)</span>
In Burglar alarm, LDR acts an AND gate.
Answer: C
Explanation
The LDR is light dependent resistor. The principle used in the working of LDR is that the resistance is inversely proportional to the intensity of light falling on the diode.
In burglar alarm, LDR diode is combined with an IC 555.
Normally an LED source is made to be incident on the LDR diode with same intensity such that the resistance will be maintained constant.
As the LDR is connected with IC, the voltage will be high when light is falling on the diode.
The IC will give only two output states that is high and low. This confirms that LDR in burglar alarm act as AND gate.
As the thief enters and crosses the LED light, the intensity of the light falling on the diode will decrease leading to decrease in the voltage which will cause the alarm to beep.
Answer:
True Explosion in antarctic sea ice levels may cause another ice age.
Explanation:
True
Using computer models, the studies show that a rise in sea ice may significantly change the ocean's circulation, ultimately resulting in a reversed greenhouse effect as ocean carbon dioxide rises and air levels decrease.
Some scientists at the University of Chicago said their analysis shows how the rise of Antarctic sea ice in cold climate could cause a cascade of shifts that could lead to turning the global climate towards glacial periods,
Answer:
C) 19 m/s
Explanation:
The motion of the cannonball is a projectile motion, which consists of 2 independent motions:
- A uniform motion (constant velocity) along the horizontal direction
- A uniformly accelerated motion (constant acceleration) along the vertical direction
As a result, we have the following:
- The horizontal velocity of the cannonball remains constant during the motion, and it is given by
where
u = 25 m/s is the initial velocity
is the angle
Substituting,
- The vertical velocity keeps changing during the motion due to the acceleration of gravity. However, at the top of the trajectory, the vertical velocity is zero:
This means that at the top of its path, the cannonball has only horizontal velocity, so its velocity is
C) 19 m/s
