When the velocity increases, then the acceleration will be positive and when the velocity decrease then the acceleration will be negative.
During the first hour, the velocity was 70 mph and during the seconds hour the velocity was 60 mph. Hence, the velocity decrease in the seconds hour. So, the acceleration will be negative during the second hour.
Now, during the third hour the velocity increases as it is 80 mph. Hence, the acceleration will be positive during the third hour.
Complete Question
A radio technician measures the frequency of an AM radio transmitter. The frequency is 14603 kHz . What is the frequency in megahertz? Write your answer as a decimal.
Answer:
The value is 
Explanation:
From the question we are told that
The frequency is 
Generally
=> 
=>
Answer: The diameter of the circular path is 2.96m
Explanation: centripetal acceleration = tangential speed^2 / radius of the circular path.
Centripetal acceleration = 2.7m/s^2
Tangential speed = 2.0m/s
Radius = 2.0^2 / 2.7 = 4/2.7
= 1.48m
Diameter = radius*2
= 1.48*2 = 2.96m.
Answer:
A
Explanation:
<em>The gold used in the making of jewelry is usually not pure but a heterogeneous mixture of metals. Pure gold is quite soft and even though it may look better in appearance compared to those made using heterogeneous mixtures, it usually bends easily. Hence, in order to make the jewelry more durable, gold is usually mixed with other metals to form a heterogeneous mixture. </em>
The correct option is A.
