Summer (but only in the northern hemisphere)
Answer:
Ratio of length will be 
Explanation:
We have given time period of the pendulum when length is 
is 
And when length is 
time period 
We know that time period is given by
So 
----eqn 1
And 
-------eqn 2
Dividing eqn 2 by eqn 1
Squaring both side
Answer: option 4: A wire that is 2-mm thick and coiled.
Explanation:
The current in each wire is same. The magnetic field due to a current carrying wire increases if the wire is coiled with the more number of turns. A thick wire would cause low resistance to the current. Hence, a 2-mm thick wire which is coiled would produce the strongest magnetic field.
Answer:
I think the answer is 0.2 m/s2
Explanation:
10km/10min is a legitimate speed. So is meters/sec, km/hour (kph), etc.
Kph is very common for vehicles:
10 km/10 min (60 min/hr) = 60 kph
