Answer:
2682
Explanation:
Work done is given by :
Work = Force x distance
= mg x d
So, work done in lifting the box of 23 kg up to my waist of 1 m high is :
W = mg x d
= 23 x 9.18 x 1
= 211.14
Now work done carrying the box horizontally 6 meters across the room is
W = mg x d
= 23 x 9.18 x 6
= 1266.84
Work done in placing the box on the shelf that is 5.7 m above the ground is
W = mg x d
= 23 x 9.18 x 5.7
= 1203.49
So the total work done is = 211.14 + 1266.84 + 1203.49
= 2681.47
= 2682 (rounding off)
Answer:
Kinetic energy is maximum when the player hits the ball.
Explanation:
Kinetic energy
, where m is the mass and v is the velocity.
So kinetic energy is proportional to square of velocity.
Velocity is maximum when the player hits the ball.
So kinetic energy is maximum when the player hits the ball.
Explanation:
Displacement = 5 km
A.
Converting km/h to m/s,
10 km/h * 1000 m/1 km * 1 h/3600 s
= 25/9 m/s
Remember,
700 watt = 700 J/s
Velocity = displacement/time
Time = 5000/(25/9)
= 1800 s
Energy = power * time
= 700 * 1800
= 1,260,000
= 1260 kJ
B.
Converting km/h to m/s,
3 km/h * 1000 m/1 km * 1 h/3600 s
= 5/6 m/s
290 watt = 290 J/s
Velocity = displacement/time
Time = 5000/(5/6)
= 6000 s
Energy = power * time
= 290 * 6000
= 1,740,000
= 1740 kJ
C.
Walking burns more energy; 1,740,000 joules. It burns more because you walk for a greater period of time.
Answer:
X: Always attractive
Y: Infinite range
Z: Attractive or repulsive
ANSWER IS C
Answer:
C)T
Explanation:
The period of a mass-spring system is:

As can be seen, the period of this simple harmonic motion, does not depend at all on the gravitational acceleration (g), neither the mass nor the spring constant depends on this value.