Explanation:
<em>Given </em>
<em>wavelength </em><em>=</em><em> </em><em>4</em><em> </em><em>m</em>
<em>speed </em><em> </em><em>=</em><em> </em><em>3</em><em>3</em><em>2</em><em> </em><em>m/</em><em>s</em>
<em>frequency </em><em>=</em><em> </em><em>?</em>
<em>We </em><em>know </em><em>we </em><em>have </em><em>the </em><em>formula </em>
<em>wavelength</em><em> </em><em>=</em><em> </em><em>speed </em><em>/</em><em> </em><em>frequency </em>
<em>4</em><em> </em><em>=</em><em> </em><em>3</em><em>3</em><em>2</em><em> </em><em>/</em><em> </em><em>frequency </em>
<em>frequency </em><em>=</em><em> </em><em>3</em><em>3</em><em>2</em><em>/</em><em>4</em>
<em>Therefore </em><em> </em><em>frequency </em><em>is </em><em>8</em><em>3</em><em> </em><em>Hertz </em><em>.</em>
Answer:
100 newtons
Explanation:
Given,
Jamal pushing a large box by a force, F = 100 N
Work done on the large box is, W = 0
It is because the applied force is less than the force of the friction between the two surfaces.
Yet, there will be a force that is exerted by the large box on Jamal.
According to newton's third law of motion, every action has an equal and opposite reaction. The reaction force is in the direction opposite to the force of action. But, their magnitude remains the same.

Hence, If the action force is 100 N, then the reaction force should be in 100 N
Answer:
525 Bq
Explanation:
The decay rate is directly proportional to the amount of radioisotope, so we can use the half-life equation:
A = A₀ (½)^(t / T)
A is the final amount
A₀ is the initial amount,
t is the time,
T is the half life
A = (8400 Bq) (½)^(18.0 min / 4.50 min)
A = (8400 Bq) (½)^4
A = (8400 Bq) (1/16)
A = 525 Bq