They attract and stick together
Chameleon's tongue is more fast than thought. Its long sticky tongue moves at an amazing ballistic speed which lashes out unsuspecting insects and bugs. Now let us see how fast it is.
GIven:
acceleration of the chameleon's tongue- 260 m/s
2 for 20 ms
constant speed 30 ms
50 ms total time
1/20 of a second
solution:
<u>260</u> = <u> n</u><u> </u>
20 50
<u>20 n </u>= <u>13, 000</u>
20 20
n= 650 m/s
Answer:
Load
Explanation:
A normal power supply can deliver up to certain amount of power to a load. The output power can be calculated multiplying Voltage (V) x Current (A). It happens that after a certain period of time, the power source's main components begin to wear, thus losing its ability to deliver its nominal power. Normally, when no load its connected to the source, you will get the operating Voltage, but when the load demands power, the ability to deliver power to it may fail to reach nominal levels. When connected, there may be voltage drops (thus, less power output) causing malfunctions turning it into a non-operative power supply.
Based on the answer provided, it seems the writer wanted you to assume that the energy loss per plank is constant. This is not the same as the bullet losing <span><span>1/nth</span><span>1/nth</span></span><span> of its velocity per plank (however, the fact that the question does not mention this assumption arguably makes the question ambiguous).
</span><span>With this assumption, the energy loss becomes
</span><span>
ΔE = <span>1/2 </span>m<span>v2 </span>− <span>1/2 </span>m <span><span>(<span>v−<span>v/n</span></span>) </span><span>2
</span></span></span>
and the number of planks <span>NN</span><span> becomes
</span>
N = <span><span><span>1/2</span>m<span>v2 /</span></span><span>ΔE </span></span>= <span><span>n2/ </span><span>2n−1
</span></span>
Otherwise, if you assume that the bullet loses <span><span>1/<span>nth</span></span><span>1/<span>nth</span></span></span><span> of its velocity per plank, then the answer is </span><span><span>N=∞</span></span><span><span>
</span>
</span>
Answer:
B) Tommy had a positive acceleration between noon and 12:30 pm.
Explanation:
Acceleration is defined as the rate of change of velocity:
where
v is the final velocity
u is the initial velocity
t is the time
In the problem,
- At noon, Tommy is walking at a velocity of 4 mi/h
- At 12.30 pm, Tommy is walking at a velocity of 6 mi/h
- A time of half an hour (0.5 h) passed between the two moments
So Tommy's acceleration is
and the acceleration is positive, since the velocity has increased.
