I'll assume you are looking for the mass of the object, since that is the missing piece of the puzzle.
The important equation for heat and energy is
Energy = mass × specific heat × change in temperature
Things we know:
Energy needed is 350 J.
Specific heat = 1.2 J/g°C
Temp. change = (30-20)°
Now we just need to plug those in and rearrange the formula to find the mass!
350 = mass × 1.2 × 10
Explanation:
Average speed = distance / time
|v| = (7 km + 2 km) / (2 hr + 1 hr)
|v| = 3 km/hr
Average velocity = displacement / time
v = (7 km east + 2 km east) / (2 hr + 1 hr)
v = 3 km/hr east
The most sense substance is the one whose mass is packed into the smallest volume. Choice-d is the smallest volume.
Answer:
1200 W
Explanation:
Power is given by the ratio between work done and time taken:

where W is the work done and t the time taken.
In this problem, W = 3600 J and t = 3.0 s. Therefore, the power in this exercise is

(a). By the inertia, it's difficult to stop heavier mass than lighter mass.
As, moment of inertia is directly proportional to the mass of the body.
Thus, more force is required to stop the boy with heavier mass than lighter mass.
The problem statement for the given case is,
The time taken by the heavier body to stop swinging is more than the lighter body, then what is the impact of weight on the time period of the swing?