C.
hope that helped you!!!
The graph between the strength of the magnet(number of paper clips picked) and battery is approximately a straight line.
For 25 coil, with increase of 1.5 V battery voltage, the electromagnet picks about 5 more clips. So, for a 7.5 V battery, it would pick about 30 paper clips.
For 50 coil, with increase of 1.5 V battery voltage, the electromagnet picks about 15 more clips. So, for a 7.5 V battery, it would pick about 30 paper clips.
Answer:
speed of each marble after collision will be 1.728 m/sec
Explanation:
We have given mass of the marble 
Velocity of marble 
Its collides with other marble of mass 25 gram
So mass of other marble 
Second marble is at so 
We have to find the velocity of second marble
From momentum conservation we know that
, here v is common velocity of both marble after collision
So 
v = 1.428 m /sec
So speed of each marble after collision will be 1.728 m/sec
Answer:
v = 4.18 m/s
Explanation:
given,
frequency of the alarm = 872.10 Hz
after passing car frequency she hear = 851.10 Hz
Speed of sound = 343 m/s
speed of the jogger = ?
speed of the


v_o = 872.1 - 10.5

The speed of jogger


v = 4.18 m/s