- Cuál es el área mínima de un bloque de hielo flatando en el ugua para poder sustentar a un aulomóvil que pesa 1200 kg f?. El bloque tiene una altura de \( 2 \mathrm{~mm} .\left(\rho_{\text {hielo }}=0,9 \mathrm{gf} / \mathrm{cm}^{3}\right) \).

- Cuál es el área mínima de un bloque de hielo flatando en el ugua para poder sustentar a un aulomóvil que pesa 1200 kg f?. El bloque tiene una altura de \( 2 \mathrm{~mm} .\left(\rho_{\text {hielo }}=0,9 \mathrm{gf} / \mathrm{cm}^{3}\right) \).

Two forces of magnitude 30 newtons \( (N) \) and 60 N act on an object at angles of \( 30^{\circ} \) and \( -45^{\circ} \) with the positive \( x \)-axis as shown in the figure. Find the direction and magnitude of the resultant force; that is, find \( F_{1}+F_{2} \). \( F_{1}+F_{2}=(\square) \mathbf{i}+(\square) \mathbf{j} \) (Simplify your answer, including any radicals. Use integers or fractions

Dados los vectores: \( \vec{u}=3 i-j+7 k \) \( \vec{v}=4 i+5 k \) \( \vec{w}=-5 i+2 j-k \) El producto \( (\vec{v} \cdot \vec{w}) \) multiplicado por el vector \( \vec{u} \) está representado por:

1. A ciarge of \( 2 \mu \mathrm{C} \) is placed 0.1 m away from another charge of \( -3 \mu \mathrm{C} \). Using Coulomb's law. calculate the force between them. (Assume \( \left.k=8.99 \times 10^{9} \mathrm{~N} \mathrm{~m}^{2} / \mathrm{C}^{2}\right)(5 \mathrm{Marks} \) ) Calculate the electric field at a point where a \( 5 \mu \mathrm{C} \) charge experiences a force of 0.2 N . ( 5 Marks) An 1 C voltage of \( V(t)=220 \sin (100 \pi t) \) is applied to a \( 50 \Omega \) resistor. Calculate the pecie current through the resistor. ( 5 Marks) A capacitor with a capacitance of \( 20 \mu \mathrm{~F} \) is connected in an AC circuit with a frequency of 50 Hz . Calculate the capacitive reactance. ( 5 Marks )

1. If you were to visit a planet that was much more massive than earth, your mass would be a) More b) Less c) The same d) Impossible to tell without knowing which planet you are visiting. 2. Which of the following is not a form of light? a) radio waves b) microwaves c) x-rays d) All of the above are a form of light. e) None of the above is a form of light