Answer:
Total Work done =0.65 joule
Explanation:
Work done is given Mathematically as
W=F *d
Where w=work done in joules
F=applied force
d= distance moved
The work done to move the toy accros the first meter is
W1=0.5*1
W1=0.5joule
The work done to move the toy across the next 2m at an angle of 30° is
.W2=0.5*2cos30
W2=0.5*2*0.154
W2=0.154joule
Hence total work done is
W1+W2=0.5+0.154
Total Work done =0.65 joule
Answer:
The temperature of the cooler substance was close to the room temperature. Therefore, the system experienced less change
Explanation:
Generally, in a closed system containing two bodies at different temperatures, there is a flow of heat energy from the body at a higher temperature to the body at a lower temperature. The effect is more significant when there is a large temperature difference between the bodies. However, if the temperature difference is small or insignificant, the change will be less.
Answer:
Kinetic energy is given by:
K.E. = 0.5 m v²
Susan has mass, m = 25 kg
Velocity with which Susan moves is, v = 10 m/s
Hannah has mass, m' = 30 kg
Velocity with which Hannah moves is, v' = 8.5 m/s
<u>Kinetic energy of Susan:</u>
0.5 m v² = 0.5 × 25 kg × (10 m/s)² = 1250 J
<u>Kinetic energy of Hannah:</u>
0.5 m v'² = 0.5 × 30 kg × (8.5 m/s)² = 1083.75 J
Susan's kinetic energy is <u>1250 J </u>and Hannah's kinetic energy is <u>1083.75 J</u>.
Since kinetic energy is dependent on mass and square of speed. Thus, speed has a greater effect than mass. As it is evident from the above example. Susan has greater kinetic energy due to higher speed than Hannah.
Explanation:
It is given that,
Diameter of the semicircle, d = 45 m
Radius of the semicircle, r = 22.5 m
Speed of greyhound, v = 15 m/s
The greyhound is moving under the action of centripetal acceleration. Its formula is given by :
We know that, 
Hence, this is the required solution.
