| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
Determine the density of the unknown liquid.
How was the buoyant calculated?
Answer: $820\ \frac{kg}{m^3}$
Exercise 3.3 D
| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
In which liquid does the object have a greater buoyant?
Answer: Buoyant is greater in the first liquid, water.
Exercise 3.1 D
| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
Is the pressure in the tire according to the manufacturer's recommendations?
Answer: No.
Exercise 1.1 G
| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
Determine the highest and lowest temperature of the day and also temperature at the moment of measurement.
Answer: $t_{highest}=38\ °C$
$t_{lowest}=23\ °C$
$t_{at\ the\ time\ of\ measurement}=27\ °C$
$t_{lowest}=23\ °C$
$t_{at\ the\ time\ of\ measurement}=27\ °C$
Exercise 4.11 A
| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
Determine the electrical resistivity of wirewound resistor.
Answer: ${\rho=129\cdot10^{-8}\ \Omega m}$
Exercise 4.4 B
| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
Determine the electromotive force (emf) of the unloaded battery and short-circuit current.
Move results to the (I, U) -coordinate system, $U=E-R_{s}I$
Answer: $E=1,58 V$
$I_{short-circuit}=6,28 A$
$I_{short-circuit}=6,28 A$
Exercise 4.2 J
| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
Determine the resistance of the wirewound resistor per unit length.
Answer: $40{,}5 \Omega /m$
Exercise 4.2 I
| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
Determine the resistance of the wirewound resistor per unit length.
Answer: $40{,}7 \Omega /m$
Exercise 3.13 D
| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
Determine the moment of inertia of the wheel through its center.
${\Sigma M=\frac{dL}{dt}}$
Answer: $0{,}073 kgm^2$
Exercise 3.1 C
| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
How much pressure was in the balloon? The red liquid in the tube is water.
Answer: 102 kPa