Answer:
1. False
some metals are ferromagnetic
2.True
3. True
4. True
5. False
The strength of electromagnetic can be increased by increasing the number of wire around it
D. both B and C will cause gas pressure to decrease because adding more gas is like adding more energy and reducing the space (volume) the atoms will move more quickly but won't have space, therefore pressure will increase.
Answer:
The frequency must be: 
Explanation:
If the work function of the metal (
) is 3 eV, then we can use the formula for the kinetic energy of an ejected electron:

considering for the minimum KE = 0, and using the Plank constant h in eV s as: 4.14 * 10 ^(-15) eV s, to solve for the frequency:

This information could be used in the following ways: the braking distance of a skidding car will depend on its initial speed and the coefficient of kinetic friction.
Thus, if the coefficient of friction is known the initial speed can be determined from the length of the skid marks.
What do you mean by Initial speed?
Initial speed can be described as how fast an object travels when gravity first applies force on the object. It can be represented in the form of (u) and is generally measured in metres per second (m/s).
It can be represented in three ways.
- v2=u2+2as
- v=u+at
- s=ut+0.5at2
Through these formulas we can calculate the initial speed of any object. It helps in understanding various velocities, time principles.
To know more about initial speed from the given link
brainly.com/question/26116359
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Answer:
Walking burns up more energy,1740000J
Explanation:
Given that the displacement is 5.0km, and running at 10km/h and uses, walking at 3km/hr and uses 290watts:
Energy consumption for running is calculated as:

Energy consumption for walking is calculated as:

Walking is a slower process hence the need for more energy over longer periods raltive to running the same distance.
Hence walking burns more energy; 1,740,000J. It burns more because you walk for a greater period of time.