1.Record her observation with the time it was hot.
2. Gather info about the pavement and its surroundings. Find out what it's made of and what its temp. is at different times of the day.
3. Come up with a hypothesis about why it is hot.
4. Design an experiment to test the hypothesis. If she thinks the Sun is responsible (which she should b smart enough to know), keep it covered during the day time and check it's temp.
5. Come up with a conclusion. If her hypothesis is not supported, design a new experiment or gather more info.
Answer:
E. The wheel with spokes has about twice the KE.
See explanation in: https://quizlet.com/100717504/physics-8-mc-flash-cards/
Answer: magnitude of the magnetic field at a distance of 19.4 cm from the wire=4.29mT
Explanation:
According to Biot-Savart law, A magnetic field generated by a current carrying wire at a distance is represented as
B=μ₀I/ 2πr
B = magnetic field intensity 1000 mT =1T, 6.50mT = 6.50 X 10^-3T
μ₀ =permeability of free space 4π × 10−7 H/m
I = current intensity
r = radius, 100cm = 1m, 12.8 cm= 12.8 x 10^-2m
6.50 X 10^-3 = μ₀ x I/ 2 π X 12.8 X 10^-2
I =6.50 X 10 ^-3 X 2π X X 12.8 X 10^-2/ 4π × 10−7 H/m
I= 4160 A
when the magnetic field is at 19.4 cm from the wire
B=μ₀I/ 2πr
= 4π × 10−7 H/m x4160/ 2π x 19.4 x 10^-2
=0.004288
= 4.29x 10 ^-3T
= 4.29mT
F(of spring)=230x=ma=3.5(5)=17.5=230x; x=0.07m.
The more arms it has the less of a chance the prey has to swim away.
