Ocean currents are caused by density differences in the water and move water masses through the deep ocean
The speed after 21 s is 18.9 m/s and the total time required for the train to reach a speed of 34 m/s is 14.4 s
<h3>
What is Speed ?</h3>
Speed is a distance travelled by a body per time taken. It is a scalar quantity and it is measured in m/s
Given that at Initially stationary, a train has a constant acceleration of 0.9 m/s2.
(a) What is its speed after 21 s?
- Acceleration a = 0.9 m/s²
Using v = u + at
Substitute all the parameters into the equation
v = 0 + 0.9 x 21
v = 18.9 m/s
(b) What is the total time required for the train to reach a speed of 34 m/s?
Let first calculate for total distance by using
v² = u² + 2as
34² = 18.9² + 2 × 0.9 × S
1156 = 357.21 + 1.8S
1.8S = 1156 - 357.21
1.8S = 798.79
S = 798.79 / 1.8
S = 443.8 m/s
v = u + at
34 = 21 + 0.9t
0.9t = 34 - 21
0.9t = 13
t = 13/0.9
t = 14.44s
Therefore, its speed after 21 s is 18.9 m/s and the total time required for the train to reach a speed of 34 m/s is 14.4 s
Learn more about Speed here: brainly.com/question/24739297
#SPJ1
Answer: False
Explanation: When a switch is closed the circuit is closed and thus the flow of current is on while when the switch is open, the circuit is open, and therefore there will be no flow of current in the circuit.
The Angle between horizontal and 1.25 plane
Detergents are special, powerful cleansers that can break up dirt, oils, and grease in clothing or on dishes.
Cleaning solvents are used to remove oil, grease, solder flux, and other contaminants.
Acid cleaners are generally used to remove mineral deposits and are useful for descaling dishwashers or removing rust from restroom facilities.
Abrasive uses
* Buffing.
* Honing.
* Drilling.
* Grinding.
* Sanding.
* Polishing.
* Cutting.
* Sharpening.